Duplication of gene on X chromosome causes gigantism

Two is often better than one, but not when it comes to DNA and RNA derived human chromosome. Researchers now believe gene duplication in a particular region, key in regulating childhood growth is a rare condition called gigantism responsible.

"Find the person responsible for the gene of child proliferation would be very useful, but the issue is much broader which regulates growth," Constantine Stratakis, lead author of the new study, said in a press release .

Gigantism is a rare disease in which children grow up quickly. Those affected usually develop abnormally high; Gigantism can delay patients also have puberty, oversized hands and feet, and diplopia.

To locate problematic genes, researchers employed in the national Institutes of Health analysis of the whole genome to study the DNA of 43 people with gigantism. The chromosomes of people were affected with a rare disease then compared to family members who were born without the defect.

The analysis showed that the gene duplication varies among study participants, the researchers were able to get the offending portion of the X chromosome to refine some four duplicated genes. Scientists have identified the gene responsible for gigantism probably GPR101.

"We believe GPR101 is an important regulator of growth", Stratakis said.

Gene duplication, which results in gigantism leads to dysfunction of the pituitary gland, which produces pea-sized gland, growth hormones. The researchers found an activity of GPR101 was 1000 times stronger than normal in affected children and extended overactive pituitary gland.