Genetic Clues to insulin production
A study published in the journal Nature Genetics shows that there are three new genetic variants underlying diabetes. These gene variants -called TBC1D30, KANK1 and EAP-are associated with insulin production and individuals that carry these variants are more prone to develop diabetes than the non-carriers.
The researchers reached these conclusions by exome genotyping array, a method less expensive than genetic sequencing and efficient in studying rare variants. Karen Mohlke, PhD, one of the study’s senior authors and associate professor of genetics at the University of North Carolina School of Medicine, said that exome genotyping array helps to analyze a large number of individuals efficiently. She also said she hopes by this method to discover new findings about other common diseases such as cancer and obesity.
The sample of 8229 Finnish males which researchers used for this study was selected from another large health study conducted by scientists at University of Eastern Finland. Now researchers want to see how these gene variants lead to diabetes. Mohlke added that studying variants of genes helps scientists understand how they affect health.
Diabetes, which affects more than 25 million people living in the United States, is characterized by a lack of insulin production. Researchers believe that the behind this disease is not a single gene, but many genes that, through interaction with environmental factors, lead to diabetes.
There are two major types of diabetes: type I diabetes, which usually occurs in lean and young individuals, and type II diabetes, which usually occurs in individuals over the age of 45 years and obese or overweight. It should be mentioned that type II diabetes represents over 80% of cases of diabetes. There are also other types: gestational diabetes, diabetes induced by drugs (corticosteroids, for example), MODY (maturity onset diabetes to the young) etc., but these are relatively rare.
Although it is a disease that does not hurt, diabetes is a severe condition because over time leads to serious complications: retinopathy, nephropathy, diabetic gangrene, diabetic neuropathy etc.. For example, retinopathy is the leading cause of blindness in individuals aged between 20 and 65 years. Retinopathy is one of the microvascular complications of diabetes along with renal disease and cardiovascular disease.
Kidney disease or diabetic nephropathy, which is manifested by microalbuminuria, that is loss of albumin in the urine, and decreased glomerular filtration rate, finally leads to dialysis. Another serious complication is cardiovascular disease. It should be noted that cardiovascular disease is the leading cause of mortality in individuals with diabetes. It is therefore very important screening the patients at risk and treating the disease before the occurrence of these complications.