Genetic link found between mental disorders, type 2 diabetes

US researchers have identified a genetic connection between some mental health disorders and type 2 diabetes.

The researchers from the University of Massachusetts in the US showed that a gene called "DISC1," which is believed to play a role in mental health disorders, such as schizophrenia, bipolar disorder and some forms of depression, influences the function of pancreatic beta cells which produce insulin to maintain normal blood glucose levels.

"Our hope is that the association we've found linking disrupted DISC1 to both diabetes and psychiatric disorders may uncover mechanisms to improve therapies, even preventative ones, to alleviate suffering caused by both illnesses which are extraordinarily costly, very common, often quite debilitating," said Rita Bortell, researcher at Massachusetts University.

The researchers studied the function of DISC1 by comparing two groups of mice. The first group was genetically manipulated to disrupt the DISC1 gene only in the mouse's pancreatic beta cells. The second group of mice was kept normal.

The mice with disrupted DISC1 gene showed increased beta cell death, less insulin secretion and impaired glucose regulation while the controlled mice were found to be normal, the researchers elucidated, in the study published in The FASEB Journal.

The researchers found that DISC1 works by controlling the activity of a specific protein (GSK3ß) already known to be critical for beta cell function and survival.

Inhibition of GSK3ß resulted in improved beta cell survival and restored normal glucose tolerance in mice with disrupted DISC1, the researchers said.