Diet in pregnancy could affect DNA and risk of diabetes

What a woman eats during pregnancy could have a bearing on their child developing type 2 diabetes, researchers have found.
Diet, stress, smoking and other environmental factors together with genetic influences in the womb known as the in-utero environment can influence the genetic make-up of babies.
Until the breakthrough, researchers have not been able to fully interpret the way people inherit conditions, including type 2 diabetes, as well as obesity.
Scientists now say this ‘developmental programming’ might be contributing to a rise in obesity, according to a study in Science.
They have discovered that the genetic variation of ribosomal DNA (rDNA) – which is genetic material that forms protein-building ribosomes in the cell – might guide how the womb’s environment determines a baby’s attributes.
Lead researcher Professor Vardhman Rakya, from Queen Mary University of London, said: “The fact that genetic variation of ribosomal DNA seems to play such a major role suggests that many human genetics studies could be missing a key part of the puzzle. These studies only looked at a single copy part of individuals’ genomes and never at ribosomal DNA.
“This could be the reason why we’ve only so far been able to explain a small fraction of the heritability of many health conditions, which makes a lot of sense in the context of metabolic diseases, such as type 2 diabetes.”
How a low-protein diet of eight per cent protein and a normal diet of 20 per cent protein impacted the offspring of mice was compared. Significant differences were eventually found in the ribosomal data when the DNA was examined.
Professor Rakyan added: “When cells are stressed, for example when nutrient levels are low, they alter protein production as a survival strategy. In our low-protein mice mothers, we saw that their offspring had methylated rDNA.
“This slowed the expression of their rDNA, which could be influencing the function of ribosomes, and resulted in smaller offspring – as much as 25 per cent lighter.”