Another bad night People who struggle to sleep six times more likely to develop diabetes
Disrupted sleep can also lead to heart disease
A bad night's sleep can often leave you feeling tired and irritable.
And now, those who continually toss and turn are six times more likely to develop diabetes and heart disease.
New research found that the symptoms of diabetes developed after just three days of disrupted sleep.
The latest findings, published in Nature
Genetics, could help to explain previous research that has shown night
shift workers are prone to type 2 diabetes and heart disease.
Fatal A lack of sleep could increase the risk of developing heart disease
The study involving almost
20,000 participants found those with any of four particular variants of the gene
were at much greater risk – offering hope of personalised treatments for
Scientists say the faulty protein, known as MT2, may disrupt the link between our 24 hour, or circadian, rhythms and release of the hormone insulin – leading to abnormal control of blood sugar and, hence, type 2 diabetes.
Professor Philippe Froguel, of Imperial
College London, said: 'Blood sugar control is one of the many processes
regulated by the body’s biological clock.
'This study adds to our
understanding of how the gene that carries the blueprint for a key
component in the clock can influence people’s risk of diabetes.
“We found very rare variants of the MT2 gene that have a much larger effect than more common variants discovered before.
'Although each mutation is rare, they are common in the sense that everyone has a lot of very rare mutations in their DNA.
'Cataloguing these mutations will enable us to much more accurately assess a person’s risk of disease based on their genetics.'
Symptoms of Type 2 diabetes developed after just three days of interrupted sleep
Dr Iain Frame, director of research at
Diabetes UK, said: 'Genetic studies like this one are useful as they
can help us understand how a person’s genetic makeup can influence their
risk of developing type 2 diabetes.
HOW THE STUDY WORKS
In the study, researchers examined
the MT2 gene in 7,632 people to look for more unusual variants that
have a bigger effect on disease risk.
They found 40 associated with type 2
diabetes, four of which were very rare and rendered the receptor protein
completely incapable of responding to the hormone melatonin.
scientists then confirmed the link with these four mutations in an
additional sample of 11,854 people.
Each mutation was analysed by testing what effect they have on the MT2
receptor in human cells in the lab.
The mutations that completely
prevented the receptor from working proved to have a very big effect on
diabetes risk, suggesting there is a direct link between MT2 and the
'This risk is not controlled by one
single gene, however, and we already know that other genetic changes, as
well as lifestyle factors, can affect the likelihood of developing this
'The more we understand about the
effect of these genetic differences, the more likely it is that we will
be able to design new drugs or apply existing drug treatments for people
with type 2 diabetes, but we are not yet at that stage.
'What we can be sure of now is that
eating a balanced diet rich in fruit and vegetables, maintaining a
healthy weight and being more physically active can help to reduce the
risk of developing type 2 diabetes as well as help people with the
condition to manage it more effectively, and lower the likelihood of
developing serious complications.'
In 2008, a genetic study led by the same team discovered people with common variations in the gene for MT2 have a slightly higher risk of type 2 diabetes.
The release of insulin, which regulates blood sugar levels, is known to be regulated by melatonin.
The body’s sleep-wake cycle is controlled by melatonin, which has effects including drowsiness and lowering body temperature.