Rare and severe hypoglycemia could be genetic

By Dr. Ananya Mandal, MDOct 10 2011

According to researchers a rare and severe form of hypoglycemia (very low levels of sugar in the blood) could be genetic.

The life-threatening condition depicts the fact that the body does not have enough energy to function. Scientists at the University of Cambridge say mutations in the AKT2 gene are to blame. Writing in the journal Science, they say there are already cancer drugs which target a similar process.

Hypoglycemia can be caused by a disruption in the balance between the hormone insulin and sugar. Insulin lowers the level of sugar in the blood. The condition is commonly associated with Type 1 diabetes, when the patients inject too much insulin, miss a meal or drink alcohol.

However, one-in-100,000 babies are born with a genetic defect which means they develop hypoglycemia even when there is no insulin in the blood. In theory they should have very high blood sugar levels. These patients have to have a feeding tube inserted directly into the stomach to prevent fits while they are asleep.

One of the researchers, Dr Robert Semple, said, “Fear of low blood sugar has dominated the lives of these patients and their families.” By examining the genetic code of three children who suffered from this rare form of hypoglycemia, scientists were able to identify the genetic alteration responsible for the disorder. In all three children, but none of their parents, a single change in the AKT2 gene was identified.

According to scientists, AKT2 plays a critical role in regulating insulin's signal to the body tissues. A slight alternation to the gene leaves this signal turned partly on, causing the body to act as though insulin is constantly present, thus lowering blood sugar levels.

Lead researcher Prof Stephen O'Rahilly said that cancer drugs were available which targeted AKT1 and which also act against AKT2. “There are actual pills that can be swallowed by humans, there could be a treatment in a year,” he assured.

“Offering families an explanation for a rare disease is usually of great value to them in its own right,” said Dr. Robert Semple, from the Institute of Metabolic Science at Cambridge, said on the university's site. “[B]ut in this case it is particularly exciting that our findings open the door for a new and specific treatment in the future.”