23 February 2015
ByAppeared in BioNews 791
BBC Word Service, Sunday 18 January 2015
The philosopher AC Grayling introduced the first of this year's 'Exchanges at the Frontier' BBC World Service broadcasts. He was joined in the Wellcome Collection hall by sixth-formers from London schools, with more students from as far afield as Ghana and Brazil linked in.
Genome sequencing was up for debate, reflecting the huge impact that the Human Genome Project has had on the public imagination. Even the opening music to the broadcast had apparently been composed using DNA.
AC Grayling started by asking the students: 'Who would like to have their genome sequenced to know what lies in store in the way of cancer, Alzheimer's disease, Parkinson's disease?'
The majority of students in the room would not, it transpires. In response, a student in Brazil argues in favour, because he saw the problems a late Parkinson's diagnosis caused for his uncle. Others quickly rebut this, saying that most people would not be able to handle the information.
So, within the first minute, it is already clear that genomic sequencing is something of a Pandora's Box; or, as AC Grayling calls it, 'a modern dilemma'. This dilemma has been building since the first human genome was fully sequenced in 2003.
Professor Nazneen Rahman, welcomed like a rock star with whoops and applause, explains some of the scientific complexities. She's head of genetics and epidemiology at the Institute of Cancer Research, and head of the cancer genetics clinical unit at the Royal Marsden Hospital in London. She's worked with Professor Mike Stratton, one of the discoverers of the BRCA2 gene.
Mutations in BRCA2 dramatically increase a person's risk of breast cancer. Accordingly, the BRCA test is one of the best-known gene tests in medicine. Professor Rahman explains this test in some detail, and so the broadcast is a good source of information for those considering undergoing it.
Professor Rahman is a 'disease detective' who studied medicine before doing a PhD in genetics. She debunks the myth that science is not as creative as the arts, presumably aiming to encourage the young scientists in the audience. However she also admits to becoming an 'accidental scientist' after deciding to do a spell of research while pregnant and not wanting to do the long hours that medicine demands.
But fitting the complexity of the genome into a fifty-three minute broadcast is a tall order, and cracks occasionally show. Professor Rahman briefly mentions imprinted genes, but then quickly steers away from the thorny issue of epigenetics.
So, what are we to conclude about genomic sequencing from the discussion? Professor Rahman stresses that genetic tests don't yet provide perfect information, and why this is a reason that people are wary of having them. There are so many genetic and environmental factors involved in developing most complex conditions (including cancer) that tests can still only estimate the risk. However she does argue firmly in favour of genetic sequencing for those already diagnosed with a disease, as it allows for more personalised medicine.
The discussion is guided in the first part by intelligent questions from the students. Indeed, some are surprisingly technical, such as Orla from London who asks about false positives and negatives in screening. The show is more informative than entertaining although AC Grayling does make a terrible pun on the word gene, asking Rahman if she's 'hunting for Levis'. Nevertheless the broadcast is frequently fascinating, and can be recommended to both genetics experts and beginners.
The latter part of the broadcast moves into more ethical questions, such as - should we screen babies' genomes as soon as they're born? Professor Rahman vetoes discussion of 'designer babies', as 'at the moment' nothing can be done genetically to influence intelligence, or any non-health-related attributes. Questions of genetic discrimination - which is illegal in the UK - are raised. Professor Rahman politely sidesteps the idea of government regulation on genome sequencing itself by saying that scientists are working for the good of the human race.
Despite her great expertise in genetic testing, Professor Rahman hasn't had her genome sequenced. Much like the majority of students who were polled at the start of the broadcast, she wouldn't choose to; saying she prefers surprises, even unwelcome ones.