Growing Up Too Fast: Precocious Puberty's Gene Link

The case offers the first evidence of a genetic culprit for the problem.

ByABC News
February 13, 2008, 7:27 PM

Feb. 14, 2008— -- Think back to the drastic changes with which your body was assaulted when you hit puberty. Now, try to imagine the same set of changes happening when you were 8 years old.

Such is the plight of children who experience precocious puberty a condition in which their bodies begin to mature years too early.

Now, for the first time, researchers have found a gene mutation that could be responsible for a small number of these cases.

"This is the first known genetic cause of precocious puberty," says lead study author Dr. Ursula Kaiser, chief of the division of endocrinology, diabetes and hypertension at Brigham and Women's Hospital in Boston, Ma. "It points additionally to the role of genetics in the timing of puberty."

The finding will be published in the upcoming issue of the New England Journal of Medicine.

Kaiser says that the gene in question was first identified a few years ago as having a role in reproductive health. In these cases, however, a flawed version of the gene was found not in those who underwent early puberty, but instead in patients who failed to go through puberty altogether.

To learn more, Kaiser collaborated with a research group in Brazil, comparing the DNA of about 53 girls who had gone through early puberty to 150 normal female subjects who had not gone through early puberty.

The mutant gene was only found in one 8-year-old girl who had gone through early puberty and none of the normal women. The researchers believe the mutant gene led to an early surge of the sex hormone estrogen, which subsequently set the chain of events associated with puberty into motion.

Kaiser says this suggests that the gene may well act as a genetic "switch" for puberty though she and endocrinologists not involved with the research agree that the mutation itself is not a common cause of the condition.

"This particular gene, at least, does not appear to be a common cause of precocious puberty," says Dr. Mark Groshek of the departments of pediatrics with Kaiser Permanente Colorado. "It opens a door, though, to suggest it may be possible to find other genes that explain precocious puberty in other children.