Scientists say they have discovered a gene that causes puberty to start unusually early.
Central precocious puberty happens when a child hits puberty before age 9. Nutrition, environment and socio-economic status all are believed to have a hand in the changes, but the role of genetics is thought to be particularly significant. Some genetic studies have shown that more than 27% of early puberty cases are hereditary.
In order to identify the genetic causes of early puberty, the researchers conducted a gene sequence analysis of 40 members of 15 families with central precocious puberty.
Their results, published in the New England Journal of Medicine, reveal that the gene MKRN3, which is passed along by the father, is the culprit. The researchers found that four mutations of the MKRN3 gene cause early activation of reproductive hormones and encourage puberty.
Undergoing puberty early can be stressful for a child, and it’s also been linked to health issues later on. One study published in the Journal of Clinical Endocrinology & Metabolism found that girls who start menstruating before age 12 have a 23% greater risk of developing heart disease and a 28% higher risk of dying from a heart attack or a stroke.
Another study published in the journal Pediatrics focused on boys’ experiences, concluding that they’re approaching puberty about two years earlier than boys a few decades ago. On average, African-American boys were undergoing the start of genital growth around 9.14 years old compared to white boys at 10.14 years and Hispanic boys at 10.4 years. It’s speculated that the higher levels of obesity are partially to blame since hormones that regulate sexual development are concentrated in body fat.
Identifying gene mutations responsible for central precocious puberty could lead to early diagnosis. “The diagnosis will also help understand the role of this gene and other associated genes on how and when kids go into puberty, an area that is currently not clear,” Dr. Patricia Vuguin, a pediatric endocrinologist at Steven and Alexandra Cohen Children’s Medical Center of New York, told HealthDay.
The study will be presented June 17 at the Endocrine Society’s annual meeting.