Page URL:

Shift work has 'chaotic' effect on genes

27 January 2014
Appeared in BioNews 739

Shifting sleep patterns can dramatically affect the normal rhythm of gene expression, a study has found.

Like many animals, humans have a natural body clock, called the circadian rhythm. This regulates our sleep-wake cycles and metabolism, among other things.

By disrupting the normal sleep-wake cycles of 22 volunteers over a week, scientists at the University of Surrey showed a sixfold reduction in the number of genes being expressed in a rhythmic pattern.

'Over 97 percent of rhythmic genes become out of sync with mistimed sleep', says study author Dr Simon Archer from the University of Surrey. 'This really explains why we feel so bad during jet lag'.

The volunteers experienced 28-hour days, without the normal changes in light levels. Their sleep was delayed by four hours every day until they were 12 hours out of sync, meaning they were sleeping during the day. Blood samples were taken to test which genes were being expressed rhythmically.

The genes that lost their rhythm were involved in many important processes, such as normal gene expression and the circadian rhythm. Because these are general processes, changes in their expression could have further effects on many other biological systems.

Professor Hugh Piggins, who is a circadian rhythm researcher at the University of Manchester, and not associated with this study, told the BBC: 'The study indicated that the acute effects are quite severe. It is surprising how large an effect was noticed so quickly'.

Increasingly, shift work is being associated with enhanced risk of cancer, type 2 diabetes and heart attacks. Some studies have also linked disruptions in the circadian rhythm to illnesses such as depression (reported in BioNews 705).

'We of course know that shift work and jet lag is associated with negative side effects and health consequences,' says Professor Derk-Jan Dijk from the University of Surrey, who led this research. 'We believe that these changes in rhythmic patterns of gene expression are likely to be related to some of those long term health consequences.'

The results also suggested that changes in the expression of some genes was a result of the disrupted sleep pattern, rather than the body clock. This information could help in the search to understand the functional role of sleep.

Genetic effects of shift work examined
NHS Choices |  21 January 2014
Mistimed sleep disrupts circadian regulation of the human transcriptome
Proceedings of the National Academy of Sciences (PNAS) |  18 December 2013
Mistimed sleep disrupts human molecular clock
University of Surrey (press release) |  21 January 2014
Night work 'throws body into chaos'
BBC News |  21 January 2014
Why shift work is linked to so many health problems such as cancer and diabetes: Study finds it damages 1,500 genes
Daily Mail |  21 January 2014
4 February 2019 - by James Close 
Are you a night owl or a morning lark? The answer is influenced by at least 351 regions of the genome, a recent study has found...
3 July 2017 - by Jen Willows 
DNA repair may be reduced in people working at night time, compared with those having a night's sleep, according to new research from the US...
27 February 2017 - by Emma Laycock 
Researchers have found a set of bodyclock-controlled genes that activate in later life and times of intense stress to protect the body...
13 February 2017 - by Ayala Ochert 
Miscarriage rates following IVF appear to increase when the clocks go forward in the spring, according to a study...
8 February 2016 - by Dr Barbara Kramarz 
Scientists have used data from personal genomics company 23andMe to identify a set of genes that are linked to being a 'morning person'...
28 October 2013 - by Siobhan Chan 
A DNA-based biological clock has shown that different parts of the body age at varying rates, with breast tissue and tumour cells appearing older than the rest of the body...
2 September 2013 - by Siobhan Chan 
A 'molecular basis' of jet lag has been identified and blocked in mice by inhibiting the activity of a single gene, according to scientists...
20 May 2013 - by Dr Amina Aitsi-Selmi 
Genes believed to regulate sleep rhythm are expressed abnormally in people with major depressive disorders, scientists say...
20 February 2012 - by Oliver Timmis 
What time of day it is could influence whether or not we get an infection. A protein known to be involved in the immune system may be influenced by the body's circadian rhythm, according to researchers at Yale University...
to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.