Scientists believe they've identified a gene that causes puberty to start earlier than other children.
When a child reaches puberty before the age of nine it is called central precocious puberty.
There are many factors that could cause this phenomenon, socio-economic status, environment, and nutrition are all thought to be possible causes, but genetics may be the main deciding factor.
According to past studies, about 27 percent of central precocious puberty cases are inherited.
Researchers analyzed the genes of 40 people within 15 families that had a history; they published their findings in the New England Journal of Medicine.
The team discovered a gene called MKRN3, which is passed through from the father, can cause the strangely early puberty.
They found the gene has four possible mutations, which can cause reproductive hormones to activate in the body at a young age.
Early puberty has been linked to health issues later than life, and added stress during development. A study published in the Journal of Clinical Endocrinology & Metabolism stated girls who begin menstruation when they are younger than 12-years-old are at a 23 percent greater chance of developing heart disease later in life, they are also at a 28 percent higher risk of dying from a stroke or heart attack.
A study published in the journal Pediatrics which focused on boys going through early puberty found they developed at an average of two years earlier than boys several decades ago. Researchers agreed that obesity could be to blame for these statistics, because it can trigger hormone release, which is stored in the body fat.
African American boys were reaching puberty at about the age of 9.14 years old, about a year younger than white and Hispanic boys.
"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," said Dr. Patricia Vuguin, a pediatric endocrinologist at Steven and Alexandra Cohen Children's Medical Center of New York.
