An international team of researchers, including some from the University of Oxford and the Peninsula Medical School in Exeter, have discovered two gene variants which may help to explain why small babies have higher rates of type 2 diabetes later in life.
The research has been published in the journal, Nature Genetics, and points to the fact that a lower birth rate and susceptibility to type 2 diabetes may well be genetic.
The research analysed the genomes of over 38,000 Europeans from 19 studies of pregnancy and birth. Two genetic variants showed associations with birth weight – one a gene called ADCY5, has recently been linked to increased susceptibility to type 2 diabetes.
The researchers say that individuals who inherit two risk copies of this gene variant are 25 percent more likely to develop type 2 diabetes in adulthood than those who inherit non-risk variants.
The combined effects of the gene variants are quite substantial – nine percent of Europeans inherit two copies of the genetic variant and are on average 113g lighter at birth than the 24 percent who inherit one or no copies. This effect, the researchers say, is equivalent to the reduction in birth weight caused by a mother smoking four to five cigarettes per day during pregnancy.
It has long been known that small babies are at a greater risk of developing type 2 diabetes later in life, but not clear why. This latest research suggests that genes are also important factors as well as the mother’s nutrition and lifestyle when it comes to the baby’s growth in the womb.