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Issue 934 (22 January 2018)

 

Welcome to BioNews by email, published by the Progress Educational Trust, providing you with news, comment and reviews on genetics, assisted conception, embryo/stem cell research and related areas.

Visit the BioNews website at www.bionews.org.uk where you can subscribe for free to receive BioNews by email in one of three formats, and search the archive of more than 6,000 articles.

 

 

CONTENTS

Comment

News Digest

Reviews

 


 

Revolutionising reproduction: setting a new moral compass

22 January 2018

By Dr Cathy Herbrand

Senior Lecturer in Sociology, Centre for Reproduction Research, De Montfort University

Page URL: http://www.bionews.org.uk/page_926313.asp Appeared in BioNews 934

Is sexual reproduction still compatible with Western values? Can germline genome editing ever be considered as medicine? Can we confine ourselves to acting only on serious disorders? These were some of the provocative and complex questions addressed during the last session of the Progress Educational Trust (PET)'s annual conference 'Crossing Frontiers: Moving the Boundaries of Human Reproduction'. The session focused on the ethical challenges posed by recent revolutionising innovations in reproduction, such as artificial gametes and genome editing.

Chaired by Fiona Fox, chair of trustees at PET and chief executive of the Science Media Centre, the session opened with Dr Anna Smajdor, associate professor of practical philosophy at the University of Oslo, Norway, who questioned how human reproduction will be reconfigured and what it will seek to achieve in the context of new scientific and technological advances. In particular, Dr Smajdor discussed how the development of in vitro derived gametes (IVGs) could challenge current biological boundaries in unprecedented ways - potentially enabling single people, same sex-couples, post-menopausal women and even children to have their own genetically related children via complementary sexual gametes. Such an eventuality would mean, some have proclaimed, the end of infertility and the democratisation of reproduction.

However, Dr Smajdor elaborated that what we mean by infertility and reproduction has become quite problematic. Current definitions tend to focus on medical defects and ignore the gendered and social aspects of these issues, such as the situations experienced by same-sex couples. Moreover, she said, it is difficult to believe that treating infertility would mean helping people to be healthier, as pregnancy or IVF involve their own risks for women's health. What are we then trying to achieve through assisted reproduction? Are we really fixing medical problems or are we in fact trying, she suggested, to 'relieve the suffering caused by unfulfilled reproductive aspirations'?

Such a question has to be considered in the light of social expectations and practices of reproduction. In particular, Dr Smajor explained that while it appears crucial for many to having genetically-related offspring, women tend to have children later in life, which means that they do not use the years when they are the most fertile to have children 'naturally'. This, coupled with the possibilities of IVGs and reproductive technologies, could lead to the 'end of sexual reproduction', she suggested. Babies conceived through assisted reproduction might indeed become the norm and Dr Smajdor recommends we negotiate these new possibilities openly.

The second speaker, Philippa Taylor, head of public policy at the Christian Medical Fellowship in London, focused on the ethical issues raised by genome editing. 'We are heading in the right direction,' she said, 'but we are at a junction and need to make crucial decisions.' In her opinion, we should not accept any technological development solely because it is safe, popular or politic. She argued that such decisions need to be centred on a moral stance based on what feels right. While somatic genome editing could be acceptable and helpful as it aligns with the aim of medicine to treat and cure diseases, she contended that a more cautious approach needs to prevail in the case of germline genome editing. To her, germline genome editing is no longer medicine because there are no specific 'suffering patients' and there are potential implications for future generations who have not consented to these interventions. She asked: 'Should humans exercise this kind of power over others?'

Germline genome editing, Taylor added, is also problematic because it is likely to involve the destruction of numerous embryos - something which many people still oppose, especially when done for research purposes rather than in therapy. Finally, she warned about the risk of 'losing an openness to the unbidden' and using germline genome editing for enhancing specific traits, as the definition of disease becomes blurred. As such she argued that we should choose to continue developing somatic genome editing for therapeutic uses, but be firm in maintaining some moral milestones, and refuse germline genome editing in its totality.

By contrast, the final speaker of this session - Guido Pennings, professor of ethics and bioethics at Ghent University in Belgium - argued that it would be difficult to resist, at least for very long, the normalisation of germline genome editing for different types of disorders, once it is proved safe and efficient. Instead of focusing on possible abuses, genome editing should be thought of in relation to other technical advances, in particular those made in the field of genome screening, he said. As it is becoming increasingly easy and common for patients to have access to expanded genetic information, Pennings suggests that PGD (preimplantation genetic diagnosis) will sooner or later be replaced by germline genome editing.

In particular, he argued that while we currently test embryos for a few specific severe disorders, progress in genome screening will soon enable the identification of hundreds of possible mutations related to various disorders. In this context, and given the limited number of embryos available through IVF, it will be difficult to select embryos for PGD that will not carry one or more mutations leading to diseases, such as cancer or diabetes. Germline genome editing, Pennings concluded, is therefore likely to appear as a better, and more efficient option for parents if it prevents their child from developing these identified disorders in the future. This would, he added, have the advantage of preventing subsequent generations from facing similar complex reproductive choices.

Unsurprisingly, these thought-provoking presentations were followed by many questions and comments from the audience. The discussions focused, among other things, on the 'inevitability' of germline genome editing. As one delegate pointed out, we still have the capacity and the regulatory tools to limit how much information patients will access. Generating more genetic information will also means more uncertainty for patients, and might be difficult to interpret without the help of a counsellor. Ultimately, it was suggested, if the goal is to improve our health, it might simply be more efficient to change our lifestyle than modify our DNA.

The session ended with straw poll of the audience who were asked: 'Who would not use germline genome editing if they could avoid their child to develop some inherited diseases?' The response suggested little audience resistance to such a possibility, an outcome which is quite striking given that not too long ago, germline genome editing was still presented as the ultimate and unchallengeable taboo during ethical discussions surrounding mitochondrial donation.

PET would like to thank the sponsor of this session, the Edwards and Steptoe Research Trust Fund, and the other sponsors of its conference - the Anne McLaren Memorial Trust Fund, the ART Institute of Washington, Ferring Pharmaceuticals, the London Women's Clinic and Vitrolife.

SOURCES & REFERENCES

RELATED ARTICLES FROM THE BIONEWS ARCHIVE

15 January 2018 - by Eleanor Taylor 
The ever-expanding limits of human reproduction are creating complex ethical and political challenges. One topic that has generated much contention is the possibility of editing the genome of human embryos...
15 January 2018 - by Dr Danielle Griffiths 
'The Wild East and the Worried West: Pioneers or Outlaws?’ was the third session of the Progress Educational Trust's (PET) Annual Conference 'Crossing Frontiers: Moving the Boundaries of Human Reproduction'...
08 January 2018 - by Dr Jess Buxton 
What exactly are SHEEFs and IVGs? How might they shed light on the mysteries of early embryo development, and offer new hope to those affected by infertility? These questions were the focus of the second session at Progress Educational Trust's one-day conference 'Crossing Frontiers: Moving the Boundaries of Human Reproduction' in London on 8 December 2017...
18 December 2017 - by Dr Avi Lerner 
The Progress Educational Trust (PET)'s Annual Conference 'Crossing Frontiers: Moving the Boundaries of Human Reproduction' discussed some of the most important ethical and scientific questions facing human reproduction. The first session, chaired by Sarah Norcross, the Director of PET, tackled the very fundamentals. What is a sperm? What is an egg? And what is an embryo?...

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Drying out

22 January 2018

By Sarah Norcross

Page URL: http://www.bionews.org.uk/page_926449.asp Appeared in BioNews 934

The PET office is still drying out – the landlord's property surveyor visited this week and declared the ceiling was dry but the walls and floor are still wet. The frustration is not knowing how long it will take to dry and when someone will next come to measure the damp. I have been tempted to buy a comedy sign for the office, 'You don't need wellies to work here but they may help!'

But the team are not just sitting watching walls dry, we are completing end of grant reports, writing grant applications and starting the work we need to get done to kick start our digital transformation. The editors continue mentoring the science-writing trainees and publishing BioNews.

Sandy and I have shared an office for ten years – talking is our main way of communicating with each other and that just doesn't work so well when you have to call someone each time you want to bounce an idea about or check something. Even with modern technology it really is a challenge for us, especially as he has to leave his desk to call me so he doesn't disturb his new office. Even worse is the fact we can't make our terrible puns and share them, or rather inflict them, on Jen, Martha and Shaoni.

We are extremely grateful to all those who have made a donation to help us keep our heads above water but we have a way to go to hit our target, so please support us is by becoming a Friend of PET as detailed here, and giving us a regular donation.

Or you can help by making a donation via PayPal (click here), by text (text 'PROG23 £10' or any other amount to 70070), or by post (as detailed here).

SOURCES & REFERENCES

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Friends share closer genetics than strangers

22 January 2018

By Elizabeth Oliver

Page URL: http://www.bionews.org.uk/page_925917.asp Appeared in BioNews 934

We are more likely to share genetic similarities with our friends than with strangers because of our social structure, a new study has found.

Not only do friends tend to be genetically closer than strangers, they are on average two-thirds as similar to each other as the average married couple, according to a study published in PNAS.

Past research has suggested a likeness between the genome of spouses and adult friends but why or how this happens has been unclear.

One explanation underlying these genetic similarities may be social homophily, whereby individuals are drawn to one another based on shared characteristics such as social background or physical traits, for example height or weight, which themselves can be shaped by genetics. Another cause may be social structuring the authors write, the idea that people form friendships due to a shared social environment, which again can be traced back to genetics.

To examine this further, scientists from Stanford, Duke and the University of Wisconsin studied social and genomic data from 5500 American adolescents collected during the National Longitudinal Study of Adolescent to Adult Health.

When analysing the genome of schoolmates, the scientists demonstrated that classmates were half as genetically similar as friends and significantly more similar than unaffiliated individuals. The researchers further revealed that socially affected traits, such as body mass index and educational attainment, were more similar than traits that weren't influenced so much by social enviroment, such as height. So people weren't necessarily subconsiously seeking out friends who are genetically like them, but rather they tend to be surrounded by people of similar genetics because of where they live and the circles they move in, and that's where they make friends.

Speaking to Time, lead author Dr Benjamin Domingue at Stanford University concluded that a shared environment and background is likely to be the main factor underlying the genetic likeness observed.

'Are individuals actively selecting to be around people who are like them, or it is due to impersonal forces, such as social structures, that we all are affected by? Our evidence, with respect to friends, suggests that it's largely the effect of social structures,' he said.

The authors add that social homophily and social structuring are not mutually exclusive and may complement one another. Professor Kathleen Mullen Harris, fellow author and University of North Carolina Chapel Hill, suggests careful consideration of this 'social genome' in future social science research.

'Geneticists need to pay attention to the social context when they're estimating genetic influences on [traits] like education attainment,' she said. 'It's important to pay attention to these shared genetic effects that we speculate are really due to social structure.'

RELATED ARTICLES FROM THE BIONEWS ARCHIVE

29 January 2018 - by Professor Marcus Pembrey 
The recent demonstration that friends share more of their genetic makeup in common than two people picked at random from their population has been making the headlines...

08 January 2018 - by Charlott Repschlager 
Drinking alcohol damages blood stem cells by altering their DNA, raising the risk of developing cancer, scientists have found.
04 December 2017 - by Dr Kristien Hens and Dr Leni Van Goidsenhoven 
Popular scientific publications regularly have articles with headlines suggesting that 'autism is hereditary' or that the 'risk for developing autism' is mostly caused by genetics...
20 November 2017 - by Charlott Repschlager 
A rare genetic mutation leading to longer and healthier lives has been discovered in the US Amish community...

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New Assisted Reproduction Bill in Ireland gathers pace

22 January 2018

By Ruth Retassie

Page URL: http://www.bionews.org.uk/page_925932.asp Appeared in BioNews 934

Details of Ireland's proposed Assisted Human Reproduction Bill were revealed in a meeting of the Oireachtas Health Committee.

Ireland currently has no legislation governing assisted reproduction. The bill aims to provide comprehensive regulation across all aspects of assisted reproduction and establish an Assisted Human Reproduction Regulatory Authority to make ongoing decisions, explained the Department of Health's chief medical officer Dr Tony Holohan.

'They will have fairly significant powers of inspection and access to information to ensure that all of the practices conform to the requirements of the legislation,' he said.

Among the topics covered by Dr Holohan were posthumous assisted reproduction, extensions on IVF storage limits for teenagers with cancer, and PGD and sex selection to avoid passing on genetic conditions.

The bill will establish publicly funded access to IVF to include single people and gay couples. However, the committee advised that it will take time to create a publicly funded fertility treatment system that meets the demand. Ireland's rates for assisted human reproduction has gone up from 7589 cycles in 2009, to nearly 9000 cycles in 2016.

Posthumous use of frozen gametes and embryos by a surviving partner will be permitted within specific guidelines. The deceased person would be considered the legal parent of a baby born within 36 months from the time the person passed away.

Dr Holohan, stated: 'These provisions enable a surviving female partner to continue a parental project after the death of her partner, provided specific conditions are fulfilled. For example, the relevant parties have received counselling and given their informed consent and provided a one-year grieving period has elapsed since the partner's death.'

Commercial surrogacy will be banned, but altruistic surrogacy arrangements will be permitted and will need to be approved by the regulator. There will be a pathway to transfer legal parenthood from the surrogate to the intended parents.

The bill proposes that both PGD and sex selection be permitted to choose embryos who will be not be affected by serious genetic disorders. The regulator will develop a full list of genetic diseases that qualify, and sex selection will only be allowed for diseases that disproportionately affect one gender.

Gamete storage was also discussed, with ten years being proposed as the standard time limit. However, patients may seek extensions from the regulator, such as teenage cancer patients. The Irish Cancer Society had expressed concern that survivors of childhood cancer needed longer storage times in order for them to have enough time to access fertility treatment as an adult.

The bill will also regulate embryo and stem cell research.

RELATED ARTICLES FROM THE BIONEWS ARCHIVE

29 January 2018 - by Fiona Duffy 
The Minister for Health in Ireland on the 3 October 2017 disclosed a decision by Government to approve the drafting of a bill on assisted human reproduction (AHR) and associated research...

23 October 2017 - by Dr Michelle Rodgers 
Equity and access are among the most urgent issues for medically assisted reproduction. According to Ireland's Health Research Board, across Europe six countries offer full public funding, and 19 countries offer partial public funding...
09 October 2017 - by Georgia Everett 
For the first time couples in Ireland will be eligible for financial aid for fertility treatments, after the Government signed off new proposals last week...
09 March 2015 - by Fiona Duffy 
According to a recent press release from the Department of Health, the Irish Government is finally going to legislate for 'Assisted Human Reproduction and associated research'...
02 March 2015 - by Sean Byrne 
The Irish Minister for Health, Leo Varadkar, has announced there will be new draft legislation to regulate surrogacy in Ireland – five months after surrogacy provisions proposed in January last year were dropped from a Bill currently before the Oireachtas...
10 November 2014 - by Antony Blackburn-Starza 
The Supreme Court of Ireland has ruled that the genetic mother of twins born to a surrogate cannot be included as the children's mother on their birth certificates, saying that it is for the Irish Parliament to legislate in this area.....

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First close-ups show DNA being read in unprecedented detail

22 January 2018

By Martha Henriques

Page URL: http://www.bionews.org.uk/page_925938.asp Appeared in BioNews 934

Scientists have taken the most detailed images yet of an enzyme working its way along a strand of DNA, revealing how it reads the genetic code. The enzyme RNA polymerase III is responsible for running along the DNA and producing a read-out in the form of RNA that the cell can use to make proteins. Finding out exactly how this happens can show how healthy cells perform this essential function, as well as hinting at ways to medically intervene when cells get it wrong.

A team at the Institute of Cancer Research (ICR) in London froze yeast samples at -180 C before imaging them using a form of electron microscopy called Cryo-EM. This incredibly powerful form of microscopy can take pictures on an almost atomic scale, showing molecules that are about one 20,000th the width of a human hair. RNA polymerase III was imaged frozen in the act of transcribing DNA, with the results published in the journal Nature.

'You don't get the structure all at once, you just see individual strokes and it takes a while to see the big picture,' study author Dr Alessandro Vannini told the BBC. 'It was definitely a Van Gogh.'

After obtaining more than a million snapshots of the enzyme at work, the team pieced the pictures together using powerful computers to visualise the 3D complex formed by the enzyme and the DNA strand.

The results show how all the parts of the RNA polymerase III complex fit together and interact with each other and the genetic code. The samples were yeast, but the basic process is very similar across all organisms. The team also hopes that the results could be used to find new drug targets for cancer. RNA polymerase III is overactive in cancerous cells, in order to produce the large quantities of protein for rapid cell division and growth. The images identified five key stages for transcription. Each one of these stages could provide novel targets for cancer therapies, the researchers say.

'This beautiful study has unveiled a fundamental cog in the inner workings of cells, and one that is often exploited by cancers,' said Professor Paul Workman, chief executive of the ICR. 'It's a hugely important finding in cell biology, and I hope that in future it will lead to new treatments for cancer patients.'

RELATED ARTICLES FROM THE BIONEWS ARCHIVE

04 December 2017 - by Dr James Heather 
Two extra letters have been added to the genetic code in bacteria, bringing the number of 'letters' up to six...
04 December 2017 - by Sam Sherratt 
Close, physical contact – or the lack of it - at an early age may lead to lasting changes to the genes, suggest researchers...
20 November 2017 - by Helen Robertson 
For the first time ever, researchers have been able to film, in real-time, the activity of the CRISPR technique on a strand of DNA...

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Blood test for eight common cancers offers promise

22 January 2018

By Dr Loredana Guglielmi

Page URL: http://www.bionews.org.uk/page_925957.asp Appeared in BioNews 934

Scientists have developed a single blood test to detect eight common cancer types and their location of origin within the body.

CancerSEEK is a non-invasive screening test or liquid biopsy aimed at tracking tumour formation and progression from fragments of tumour DNA in the bloodstream. Unlike previous liquid biopsy tests which tend to assess only the presence of circulating tumour DNA (ctDNA), CancerSEEK simultaneously detects cancerous proteins. By using a combination of eight aberrant proteins and 16 ctDNA mutations, the new test is able to identify ovarian, liver, stomach, pancreatic, esophageal, colorectal, lung and breast cancers, which account for 60 percent of the estimated cancer deaths in the US.

'The use of a combination of selected biomarkers for early detection has the potential to change the way we screen for cancer, and it is based on the same rationale for using combinations of drugs to treat cancers,' said Dr Nickolas Papadopoulos, at Johns Hopkins University School of Medicine in Baltimore, Maryland, who led the study. The research was published in Science.

The test was given to around 1000 patients with non-metastatic cancers. CancerSEEK correctly diagnosed 70 percent of the cases and successfully excluded false positive results with a specificity above 99 percent. However, the performance of the test varied significantly with the type of tumour: it detected 98 percent of ovarian cancers, but only 33 percent of breast cancers. In addition, the test outcomes substantially improved when more advanced cancerous lesions - stage III diseases, were examined.

'This paper is provocative,' Professor Alberto Bardelli, at the Candiolo Cancer Institute in Turin, Italy told Nature News. 'It points to the fact that we should stop looking at a little part of the picture. Instead, we need to see all of the sources of information in the blood.'

CancerSEEK could be potentially administered by primary care providers at the time of other routine blood work, and the researchers estimate that the cost of the test could be less than US$500, comparable with a colonoscopy.

Experts noted some drawbacks of the study. 'This looks promising but with several caveats and a significant amount of further research is needed before we can even contemplate how this might play out in screening settings,' said Dr Mangesh Thorat, deputy director of the Barts Clinical Trials Unit, Queen Mary University of London. 'This is only a case-control study, and therefore needs further evaluation in large cohorts more representative of general population where such screening might be introduced.'

Researchers led by Dr Papadopoulos have begun to address those concerns and have started a new study that will test CancerSEEK in at least 10,000 healthy individuals.

RELATED ARTICLES FROM THE BIONEWS ARCHIVE

21 August 2017 - by Dr Loredana Guglielmi 
US researchers have developed a new blood test to detect cancer-related DNA alterations before patients experience symptoms...
26 June 2017 - by Charlotte Spicer 
A new three-in-one blood test could progress personalised treatment for patients with prostate cancer...
02 May 2017 - by Dr Loredana Guglielmi 
Blood tests for tumour DNA could predict relapse of the most common type of lung cancer up to one year before clinical signs show up on patient's scans...
13 March 2017 - by Dr Loredana Guglielmi 
Researchers have developed a new blood test that can not only detect cancer at an early stage, but can also indicate where the tumour is located in the body...
09 November 2015 - by Ayala Ochert 
Scientists say it may be possible to track the progress of cancer – and cancer treatment – in real time from fragments of tumour DNA that are shed into the bloodstream...

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Screening all women over 30 for BRCA could prevent 64,000 cancers

22 January 2018

By Dr Molly Godfrey

Page URL: http://www.bionews.org.uk/page_925958.asp Appeared in BioNews 934

The blanket screening of all women over 30 for genetic mutations which cause breast and, or ovarian cancer could prevent more cancers and be more cost-effective than current approaches, according to a new study.

Dr Rosa Legood at the London School of Hygiene and Tropical Medicine (LSHTM), and lead study author said: 'Our analysis shows that population testing for breast and ovarian cancer gene mutations is the most cost-effective strategy which can prevent these cancers in high-risk women and save lives. The study was published in the Journal of the National Cancer Institute.

According to mathematical models developed by the researchers based at The Barts Cancer Institute and the LSHTM, a blanket screening approach would save lives, and be more cost-effective than the current strategy of screening only women with a personal or family history of cancer. They estimate that testing all women over 30 for faulty genes could result in up to 17,000 fewer ovarian cancers, and 64,000 fewer breast cancers in the UK.

Inherited mutations in the BRCA1 and BRCA2 genes can greatly increase chances of developing breast and/or ovarian cancer in a woman's lifetime. Women carrying either of these gene mutations have a 17-44 percent chance of developing ovarian cancer and a 69-72 percent chance of developing breast cancer, while women without the mutations have a 2 percent risk of ovarian cancer and 12 percent risk of breast cancer.

If the mutations are known about, preventative measures can be taken, including enhanced screening, risk-reducing mastectomies, removal of ovaries and preventative chemotherapies, which can drastically lower the chances of cancer developing.

However, some argue that caution needs to be applied when it comes to blanket screening populations; and that the risks of overtreatment and unnecessary distress should not be underestimated. Justine Alford, at Cancer Research UK, who was not involved with the study, told Sky News: 'If we're going around and screening all women who are above the age of 30 for these particular genes, these faulty genes, are we going to pick up women who have these particular genes but might not actually develop a disease as a result of these genes?'

RELATED ARTICLES FROM THE BIONEWS ARCHIVE

15 January 2018 - by Hannah Somers 
A new study has found that BRCA gene mutations do not affect the survival rates of breast cancer patients under 40...
13 November 2017 - by Dr Loredana Guglielmi 
Researchers have introduced new criteria to screen for BRCA gene mutations that could prevent more than 10,000 cases of cancer and save more than 2000 lives in the next decade...
30 October 2017 - by Annabel Slater 
Two studies have discovered 72 new genetic variants associated with the risk of developing breast cancer...

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Loops or spirals? 150-year mystery of what happens to DNA in cell division solved

22 January 2018

By Dr Rachel Huddart

Page URL: http://www.bionews.org.uk/page_926012.asp Appeared in BioNews 934

How DNA is accurately split between cells when they divide has finally been solved by researchers.

Despite 150 years of study of the cell division process of mitosis, little was known about how DNA is arranged to make sure that each daughter cell receives a complete genome. Some scientists were convinced that the DNA was arranged into a spiral shape, while others argued that the DNA was in loops. Now, a new paper published in Science has shown that both sides of the argument are right.

Life is dependent on the ability of cells to divide their DNA equally into two new cells in mitosis. Whenever a living organism grows, replicates or repairs itself, it is reliant on successful cell division. Mistakes in this process can result in a cell missing parts of its genome or having too many copies of a certain bit of DNA. This can cause serious consequences including birth defects or formation of a tumour.

To study how cells manage to do this correctly the vast majority of the time, the team used chicken cells to track how chromosomes prepare themselves for cell division. They condense and change shape from what looks like fuzzy blob through the microscope to the more recognisable rod-like chromosome shape.

Combining what was seen in the cells with biochemical experiments and mathematical modelling, the team found that that two protein molecules known as condensins gather up DNA in each chromosome into organised loops arranged around a central helix, like stairs in a spiral staircase. This organised structure is easily divided during mitosis and helps control how much DNA each daughter cell gets.

'I find this extremely satisfying,' said Dr Job Dekker from the Howard Hughes Medical Centre, one of the researchers who led the study. 'I always aim for consilience. If you're confronted with datasets that supposedly tell you two different things, can you find a way for them both to be right?'

The findings are another step on the long road to fully understanding how chromosomes behave during mitosis. After a century and a half of investigation, 'it is brilliant to see decades of work come to fruition', said Tom Collins, a senior portfolio developer at the Wellcome Trust, which funded the research. 

'It's the beginning of a long journey towards practical applications and the next step is to take this knowledge of how the process works in healthy cells, and identify what can go wrong to cause cancer or birth defects.'

SOURCES & REFERENCES
Science | 18 January 2018
 
EurekAlert | 18 January 2018
 
Howard Hughes Medical Institute | 18 January 2018
 
Wellcome Trust | 18 January 2018
 

RELATED ARTICLES FROM THE BIONEWS ARCHIVE

28 November 2016 - by Dr Rachel Huddart 
DNA only accounts for about half of the total volume of chromosomes, as shown by new 3D images of human chromosomes...
15 December 2014 - by Simon Hazelwood-Smith 
A study into the 3D structure of the human genome has revealed the locations of DNA 'loops' at unprecedented resolution...
12 September 2011 - by Sarah Pritchard 
Researchers based in the USA and the Netherlands report study findings that may explain why women with mutations in the BRCA1 gene are more susceptible to breast and ovarian cancer...
29 March 2010 - by Dr Will Fletcher 
A recent study has lent more weight to the view that 'Junk DNA' may be anything but junk. A joint effort by the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany and Stanford University, California, US, has uncovered large differences between the non-coding DNA of different individuals, which may be associated with differing levels of disease risk and other traits too...

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Podcast Review: Naked Genetics - The Future of Genomic Medicine

22 January 2018

By Sam Sherratt

Page URL: http://www.bionews.org.uk/page_926237.asp Appeared in BioNews 934

The Future of Genomic Medicine

Naked Genetics, Thursday 14 December 2017

Presented by Dr Kat Arney

'The Future of Genomic Medicine', Naked Genetics, Thursday Thursday 14 December 2017


Over the last few years, we've seen a welcome explosion in the number of scientific podcasts aiming to spread the gospel about new research that may otherwise miss the attention of the mainstream media. With this in mind, I recently sat down to listen to an episode of Naked Genetics, a weekly podcast covering the 'latest genetics news and breakthroughs from the DNA world' in a half-hour format. The episode I caught is entitled The Future of Genomic Medicine, billed as an exploration of how novel genetic research is becoming increasingly relevant to public healthcare.

The podcast begins rather inauspiciously with an interview with Professor Michael Simpson at King's College London, a genomics expert attending the Genetics Society Autumn Meeting at the Royal Society in London. Though Professor Simpson drops in the occasional interesting factoid, more time is spent glossing over the general topics being discussed at the meeting than any explicit research, and I quickly find myself growing impatient for the next segment.

'Over the next 10 years or so, there's predictions that we're going to have up to a billion genomes sequenced and most of these are going to be sequenced in the healthcare setting,' proclaims Professor Simpson proudly, but it's not enough to hold my interest. Technological futurism is notoriously unreliable (remember cold fusion anyone?), and it's often far more fascinating to hear about specific research being performed in labs as we speak.

The next interview proves more promising. Dr Kaitlin Samocha from the Sanger Institute in Cambridge explains the challenges of trying to process enormous quantities of genetic data to produce usable results.

'One of the big questions within genetics is being able to understand any genetic changes that we see in individuals,' Dr Samocha begins. 'We really need to be able to filter out the changes that are important.'

Sounds reasonable enough so far, if a little cryptic. But with over 3 billion base pairs in the human genome and an estimated 30,000 genes capable of encoding protein, how do they parse out the noise from the real results?

'We have some very nice computers!' says Dr Samocha. 'And actually, increasingly, people are moving to cloud-based systems.' She continues: 'This allows researchers not only at the Sanger Institute where I'm based but researchers in Boston or in Germany, or a variety of places in the world to all contribute understanding the different changes in how they work together.'

The idea of a global collective of researchers sharing gigabytes of genetic data through a digital cloud is very cyberpunk, and I'm immediately hooked.

Later in the podcast, the discussion turns to CRISPR/Cas9, an experimental approach for making precise changes to the human genome. Genome editing has been making headlines for a while now and I'm familiar with the basics, but hearing about it from researchers actively working in the field still proves interesting listening.

'Let's imagine that a clinician has identified a human disease and a gene variant has been found in individuals who have that disease,' says Dr Andrew Wood, a geneticist from the University of Edinburgh. 'In order to show that that gene variant is causal for the disease, one of the approaches that researchers take is to take cells and engineer that particular variant into a cell that didn’t have it previously and to see whether or not that cell behaves differently.'

The idea of researchers being able to create customised models of disease through genome editing sounds fascinating. What really catches my attention, however, is a later interview with Dr Jakub Tolar from the University of Minnesota in Minneapolis, who describes new research investigating the use of CRISPR to treat disorders such as bone marrow failure and painful blistering skin conditions.

Dr Tolar explains how marrow or skin cells with malfunctioning DNA could theoretically be taken from a person's body, edited to express a healthy copy of the relevant gene, then reintroduced into the patient's system to treat their disease.

'There's nothing sci-fi about this,' says Dr Tolar. 'I think this is a predictable, incremental, very exciting pathway we are taking now.'

It's an amazing concept, and enough to sell me both on the merits of the research and the quality of the podcast.

Despite a slow start and the occasional dearth of specifics, Naked Genetics provides an intriguing first-hand insight into novel genetic research as told by the researchers themselves. The focus on interviewing working scientists provides a welcome degree of authority to the discussions, though at times you find yourself wishing they'd gotten someone with a little more flair for communications to help script their remarks. Still, anything that promotes such humanitarian work is a positive in my book, and it's an interesting listen overall.

SOURCES & REFERENCES

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12 February 2018 - by Ruth Retassie 
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Radio Review: Inside Science - Ancient DNA and Human Evolution

22 January 2018

By Ewa Zotow

Page URL: http://www.bionews.org.uk/page_926314.asp Appeared in BioNews 934

Inside Science: Ancient DNA and Human Evolution

BBC Radio 4, Thursday 28 December 2017

Presented by Dr Adam Rutherford

'Inside Science: Ancient DNA and Human Evolution', BBC Radio 4, Thursday 28 December 2017


The programme starts with a bold statement: 'No other field of science has experienced such an upheaval in the last few years as human evolution.' There is a reason for it: the recent addition of DNA research to the toolbox of techniques available to evolutionary scientists has led to remarkable findings.

In this programme, Dr Adam Rutherford gives a snapshot of the current state of the field of human evolution and, in particular, how genetic analyses helped to uncover previously unknown aspects of the history of our species and our near relatives. My concerns that my very limited knowledge of this field would prevent me from fully appreciating the significance of this recent 'revolution'  were unfounded; the programme was very good at highlighting the importance and scope of changes that genetics have brought to evolutionary study.

Most of what we know about our evolutionary ancestry has come from archaeological finds and the various methods for dating their age. Now, with DNA analysis, scientists have access to extra information about when and how different hominin groups lived and interacted together. This new biological evidence has changed the way we think about our evolutionary past. 

The programme was recorded mainly at a scientific meeting marking the 20th anniversary of the first successful attempt to analyse the DNA from Neanderthal bones in 1997. Technical advances had made it conceivable to study the genes of extinct species. The Neanderthal genome was fully sequenced only eight years after the human genome, allowing scientists to compare the two and investigate any biological changes that happened before and after divergence from our last common ancestor.

Although the new technology is truly extraordinary and has led to fascinating advances, Dr Rutherford is careful to give due credit to, as he calls them, the 'good old-fashioned' palaeoanthropology and archaeology. Without these, we would not be able to provide the context in which the genetic story can be embedded.

Nowadays, a lot of us still carry some Neanderthal DNA: around 1 to 2 percent of our genes have that origin. The genetic overlap is a result of 'gene flow events' between early humans and Neanderthals, which is a technical term, 'but you all know what that means', jokes Dr Rutherford. Interbreeding might have provided a quicker way of adapting to a new environment, bypassing the slow process of selection.

Rutherford is particularly skilful at pacing the material and directing attention to the main message. The programme delves into complex findings related to the movement and interaction between different hominin species. The picture painted by this new evidence is convoluted, however, the main point of the discussion is frequently reiterated and clarified, making it digestible.

New genetic evidence suggests that a type of archaic human must have interacted with the early Neanderthals at some point between the time when we first split from a common ancestor around 700,000 years ago, and the time the two species met again around 40,000 years ago when humans left Africa. Interestingly, there are no fossils to support this, and the new theory stemmed from the genetic material of early Neanderthals found recently in Atapuerca, Spain.

Overall, the show is very informative and pleasant to listen to. Dr Rutherford's genuine enthusiasm makes it easy to get excited about the new technologies and discoveries, even with relatively little prior knowledge. The show caters to anyone with a broad interest in science and general curiosity to find out more about new and exciting scientific discoveries. It provides enough information to get a good idea of the state of the current knowledge on this topic without getting bogged down in too much detail.

I wished the programme went deeper into the implications of the new findings. It briefly touches on some of them, for instance, that the gene flow events in Spain could explain the almost simultaneous spread of a type of stone tools observed in Europe and Africa. It could have benefitted from more such explanations of what the new discoveries have changed in our understanding of prehistoric technology and culture.

Even so, I found out a lot in such a short time. The host skilfully led the discussion towards most interesting points and makes sure that the main take-home message is clear and simple. I really enjoyed his appreciation of all disciplines and how they collectively enable us to see the big picture. With the exciting new technologies, it would be easy to dismiss the 'old-fashioned' methods; on the contrary, Dr Rutherford always gives credit to the fields of study that made these newest developments possible.

The list of programmes by Inside Science is long, and their subjects are broad and very topical; I will definitely be listening to another one soon.

SOURCES & REFERENCES
BBC iPlayer | 28 December 2017
 

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'The Gene: An Intimate History' is the latest book from Pulitzer Prize-winning author Siddhartha Mukherjee. Taking a similar approach to his previous work 'The Emperor of All Maladies: A Biography of Cancer', Mukherjee interweaves his personal history with a comprehensive and extensive review of the history of genetic research...
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