Is Type 1 Diabetes genetic?
There are some genetic factors that could cause type 1 diabetes to be inherited. For instance, if an person´s first-degree relative has type 1 diabetes, there is a small chance for the person to inherit it. Some people are at risk due to their genes. There are several genes that can increase the risk of developing type 1 diabetes. Two of the most researched genes are the insulin gene and the HLA Region (human leukocyte antigen).
The Insulin gene
The insulin gene is where the DNA is coded for protein insulin. This is a very important region because, firstly, it determines how susceptible one is to obtaining diabetes and, secondly, it determines how much insulin the gene can produce.
Within the insulin gene lies the VNTR (variable number of tandem repeats). There are different types of VNTR regions; a smaller one and a longer one. The former should contain between 26 and 63 DNA repeats, while the latter between 140 and 200 repeats. If an individual inherits two short VNTR regions, they are two in five times likelier to develop type 1 diabetes than an individual with at least one long VNTR.
The HLA region
The HLA region is part of a chromosome that consists of a number of genes involved in how the immune system functions. The genes are responsible for making proteins which are found in some of the cells located in the immune system. This is very important because it allows the immune system to recognize its own cells from potentially harmful bacteria or viruses.
Within this region lies two genes, one of which plays an important role in diabetes. This gene is called DR. One form of DR can be inherited from each parent. The combination of these forms is what determines the individual´s chances of inheriting type 1 diabetes.