The researchers found two genetic regions that influence birth-weight, one of which is also associated with Type 2 diabetes.
It has been known for some time that small babies are more likely to get the illness, and that a mother's diet and nutrition affect her child's weight and future risk of disease, in a process known as 'programming'. However, this is the first time a genetic link has been firmly established.
The findings are based on 19 European studies of pregnancy and birth. The research showed that one variant in a gene called ADCY5 was linked to both birth-weight and Type 2 diabetes.
People who inherit two risk copies of this variant are 25 per cent more likely to get diabetes in adulthood than those who inherit two non-risk copies, and they weigh less at birth.
"Finding two gene variants that decrease birth-weight is the first exciting step to unraveling the well known associations between birth-weight and killer diseases in later life," the Scotsman quoted Jim Wilson, Royal Society University Research Fellow at the University of Edinburgh, as saying.
"It is particularly interesting that one of these variants is also a risk factor for Type 2 diabetes. These genes will begin to reveal the biology behind how low birth-weight increases the risk of adult-onset diabetes, heart disease and high blood pressure," he added.
The study has been published in Nature Genetics. (ANI)