Researchers pinpointed a gene within a duplication is a short stretch of the X chromosome that may be linked to excessive childhood growth.
The gene in question could have a significant influence on how much children grow, the National Institutes of Health reported.
"Finding the gene responsible for childhood overgrowth would be very helpful, but the much wider question is what regulates growth," said Constantine Stratakis,
, lead author of the new paper and the scientific director of the Division of Intramural Research at NICHD.
The research team looked at a family who was treated at the NIH Clinical Center in the mid-1990s; the mother had been treated for gigantism and had two sons also being treated for the condition. People with gigantism are abnormally tall and struggle with side effects such as delayed puberty and double vision. It is caused by a defect in the pituitary gland, which is responsible for making growth hormones.
"Giants are very rare. If you have three cases in the same family, that is very rare," Stratakis said.
Most of the pituitary gland of the mother in the observed family was removed when she was 3 years old, and in adulthood and in adulthood she was only slightly above average height.
To make their findings the researchers performed a complete genomic analysis of 45 people with gigantism to determine which gene was responsible for the disorder. They found the same four genes were duplicated in all of the patients, and the team was able to narrow these down to a gene called GPR10. The gene's activity was 1,000 times stronger in children with the gigantism duplication.
"We believe GPR101 is a major regulator of growth," Stratakis said.
The researchers hope the discovery will help lead to new treatments for children with gigantism.