Genetic predispositions to diabetes: How genomic testing can revolutionise prevention

Diabetes has been recognised by the World Health Organisation as an emerging threat for a country like India. With nearly 77 million patients and 25 million pre-diabetics, there is a dire need to tackle Diabetes. Awareness, availability of special care, and focus on diet are expected to help, but newer techniques such as genome sequencing and testing are revolutionary approaches in controlling pre-diabetes. That is in cases where there is a genetic predisposition to diabetes.

Diabetes Mellitus can be broadly further classified into two categories – Type 1 and Type 2. The third category of gestational diabetes occurs during pregnancy which also has reportedly observed a spurt in cases – five million Indian women affected in 2024. Unfortunately, Type 1 diabetes may not be prevented but treated with lifestyle choices and health interventions. Type 2 diabetes on the other hand may be preventable by lifestyle and healthcare choices. But in recent days, the risks of genetic mutations have added a new complexity – monogenic diabetes.

There are three common myths when it comes to Diabetes. First, people wrongly believe that it is completely curable. Secondly, there is a popular myth that healthy people focusing on diet and gym training sessions may not contract Diabetes. Thirdly – the confusion around the different types. The severity of the ailment is such that, ignoring one’s health for long, could pose severe risks such as cardiovascular ailments, eye problems, nerve damage, impaired kidney function, weakened immune system, and the dreaded diabetic foot.  

Type-2 Diabetes is more common and reportedly affects 95 per cent of people around the world while Type-1 diabetes is caused owing to insufficient insulin production in the pancreas. As with any ailment, a wrong prognosis or delayed diagnosis affects individuals. When underlying symptoms are left untreated, there is a possibility of peripheral arterial disease and in many cases, the only option left to the medical professionals is to amputate affected feet or limbs.  

Genomic sequencing for detecting diabetes risks started becoming a practical tool in the 2000s, as scientists learned more about which genes were connected to the disease. Genomic sequencing is like reading the “instruction manual” in our DNA to find out if there are parts that might make someone more likely to get diabetes. By looking for specific changes or “markers” in certain genes, doctors can understand a person’s risk of developing diabetes and suggest ways to reduce that risk early on. This knowledge also helps them choose treatments that are more likely to work based on a person’s unique genetic makeup, which can slow or even prevent the disease from progressing.

Many people are genetically predisposed to diabetes, particularly type 2 diabetes, due to inherited gene variants that increase their risk. Many racial and ethnic groups such as Native Americans, African Americans, Hispanics, and even Asian Americans, have reported higher rates of diabetes, suggesting both genetic and lifestyle factors at play. Genetic markers associated with increased diabetes risk include variations that affect how the body regulates insulin and blood sugar levels. While such gene markers alone don’t cause diabetes, they can make individuals more susceptible, especially when combined with lifestyle factors like diet and physical activity.

Genomic testing plays a crucial role in diabetes prevention and personalised treatment by identifying genetic markers that indicate a heightened risk for type 2 diabetes. Early detection of these markers enables proactive lifestyle changes and medical interventions, reducing the likelihood of disease onset. Additionally, genetic testing can pinpoint affected family members and detect inherited gene variants in children, helping to assess their risk of developing monogenic diabetes.

Beyond risk prediction, genomic testing aids in differentiating between type 1 and type 2 diabetes, and ensures accurate diagnosis and tailored treatment approaches. By analysing specific gene mutations, doctors can identify pathological forms associated with diabetes, allowing for the selection of targeted preventive and therapeutic strategies. Developed from extensive research on gene polymorphisms linked to diabetes, this testing provides valuable insights into an individual’s susceptibility to diabetes, promoting early preventive actions to manage or prevent disease progression.