Scientists discover type 1 diabetes may be two distinct diseases

Researchers have found that type 1 diabetes may not be a single disease but rather two genetically and biologically distinct conditions.

According to Report, scientists from the US and the UK reached this conclusion after analyzing patients' first genes with respect to two HLA gene variants – DR3 and DR4. The findings were published in Diabetologia.

The study compared genetic data from 9,091 individuals with type 1 diabetes and 14,157 healthy participants. Analysis revealed significant differences not only in genetic predisposition but also in the mechanisms of disease development between patients carrying the HLA‑DR3 and HLA‑DR4 variants.

Researchers discovered that the HLA‑DR3 variant is linked to genes affecting mast cell function, which play a role in inflammation and immune responses to foreign substances.

By contrast, in the HLA‑DR4 variant, T cells play the dominant role, directly attacking the body's own cells. This autoimmune process leads to the destruction of insulin‑producing beta cells in the pancreas.

Both genetic variants increase the likelihood of the same diagnosis, but the disease may begin through different biological mechanisms. The scientists emphasized that the differences between these groups are so clear that they could be considered separate subtypes of the disease.