Washington, May 2 : A new study conducted by Canadian, French and British researchers has revealed the discovery of a DNA sequence that controls the variability of blood glucose levels in people.
The discovery, say researchers, is vital as high blood glucose levels in otherwise healthy people are often indications of heart disease and higher mortality rates.
The findings also hold promise of a personalized medicine, much closer to reality.
The study was conducted by Dr. Phillippe Froguel and colleagues at Imperial College London and le Centre national de la recherche scientifique (CNRS) in Lille, France.
In this study, the scientists looked at the genetic code of healthy, non-diabetic individuals whose blood glucose levels were in the normal range.
They found that a single DNA mutation within three different genes partly explained why some individuals have high or low blood glucose levels. According to the researchers, these genes actually affect the threshold level of glucose in the bloodstream, which triggers the secretion of insulin. This implies that the higher the threshold, the higher the blood glucose level will rise before insulin starts to regulate it.
"These sequences explain about 5 per cent of the normal variation in blood glucose levels between otherwise healthy people. Five per cent may not sound huge, but for complex traits, that's rather a lot. By contrast, hundreds of different genes influence height," explained Dr. Sladek, one of the researchers on the study.
The researchers indicated that these findings could offer important insights into the genetic mechanisms behind glucose metabolism, leading to greater understanding of the genetic roots of metabolic disorders in general.
"In theory, any medical test which has a genetic component can use this approach. That brings us to the idea of 'personalized medicine.' Eventually, we might be able to customize treatment to an individual's unique genetic structure," explained Sladek.
As high blood glucose levels also have a link with increased risk for cardiovascular disease, these findings could offer the hope of discovering new management techniques and treatments.
"It's important to know that a high blood glucose level, even within the normal and non-diabetic range, is a risk factor for early mortality. Epidemiological studies have shown that 80 per cent of the risk of cardiovascular disease is related to a blood glucose level just above the average," explained Dr. Philippe Froguel of Imperial College and CNRS.
The results of the study are published in the online version of the journal Science.
Story first published: Friday, May 2, 2008, 12:54 [IST]