Washington, May 22 : In a novel study, scientists have identified a gene that helps regulate abnormal production of sugar in the liver, critical to people with diabetes.

The liver is the sugar factory for the body - when blood sugar (glucose) levels fall, the liver makes and releases more.

In people with diabetes, especially Type 2 diabetes, the liver doesn''t stop making sugar when it should, so blood sugar levels can rise overnight while they sleep even though they haven''t eaten.

"A lot of my patients will complain that they go to bed with a blood sugar of 5 and wake up with a blood sugar of 12," said Dr Jenny Gunton, diabetes specialist and endocrinologist from Sydney''s Garvan Institute of Medical Research.

"It upsets people when their blood sugar behaves as if they''re getting up in the night and having a really big snack. I have to tell them it''s just one of those unfair things about having diabetes," she added.

Gunton and her colleagues from Boston have been studying a transcription factor, or kind of ''master regulator'', called ARNT, which controls expression of other genes involved in processes like glucose breakdown and insulin production.

In an earlier study, the group showed that there is 90pct less ARNT in insulin-producing cells of people with Type 2 diabetes.

The new study showed how ARNT might be affecting the liver.

"We''ve shown that there''s likely to be decreased ARNT in the liver of people with Type 2 diabetes compared to people without Type 2 diabetes," said Gunton.

"Working with mice, we found that glucose levels were elevated and there was glucose production from a ''precursor'', a source not normally metabolised," she added.

The study showed that to some extent ARNT is regulated by insulin, so that insulin resistance in itself will contribute to a decrease in ARNT.

If liver cells are treated with insulin, there will be a small increase in ARNT protein. The insulin will also help move the ARNT into the nucleus of the cell, where it does its job as a master regulator.

The study appears in the journal Cell Metabolism. (ANI)