Newly found diabetes gene could create treatments
A new gene thought to be critical in the regulation of insulin has been discovered in a study of families with rare blood sugar conditions.
The research team studied a family where several individuals had diabetes, while other family members had developed insulin-producing tumours in their pancreas. These tumours, known as insulinomas, typically cause low blood sugar levels, in contrast to diabetes which leads to high blood sugar levels.
They identified a genetic disorder in a gene called MAFA, which controls the production of insulin in beta cells. Unexpectedly, this gene defect was present in both the family members with diabetes and those with insulinomas, and was also identified in a second, unrelated family with the same unusual dual picture.
This is the first time a defect in this gene has been linked with a disease. The resultant mutant protein was found to be abnormally stable, having a longer life in the cell, and therefore significantly more abundant in the beta cells than its normal version.
First author Dr Donato Iacovazzo from the Queen Mary’s William Harvey Research Institute added: “We believe this gene defect is critical in the development of the disease and we are now performing further studies to determine how this defect can, on the one hand, impair the production of insulin to cause diabetes, and on the other, cause insulinomas.”
Lead author Professor Márta Korbonits from Queen Mary’s William Harvey Research Institute said: “We were initially surprised about the association of two apparently contrasting conditions within the same families – diabetes which is associated with high blood sugar and insulinomas associated with low blood sugar. Our research shows that, surprisingly, the same gene defect can impact the insulin-producing beta cells of the pancreas to lead to these two opposing medical conditions.”
Researchers from the University of Exeter and Vanderbilt University were also involved in the study, which also found that males were more prone to developing diabetes, although insulinomas were more commonly found in females.
Professor Korbonits added: “One exciting avenue to explore will be seeing if we can use this finding to uncover new ways to help regenerate beta cells and treat the more common forms of diabetes.”
The findings have been published in the PNAS journal.
Professor Sian Ellard, of the University of Exeter Medical School, who oversaw the study, said: “While the disease we have characterised is very rare, studying rare conditions helps us understand more about the physiology and the mechanisms underlying more common diseases. We hope that in the longer term this research will lead to us exploring new ways to trigger the regeneration of beta cells to treat more common forms of diabetes.”