Scientists have identified a gene which may play a key role in determining when a child hits puberty.
Some children can hit puberty earlier than others
A team of researchers in the UK and the US say the gene regulates a protein called GPR54.
Writing in the New England Journal of Medicine, they said mutations in this gene can prevent people from going through puberty normally.
The discovery could lead to new treatments for children who go through puberty very early or not at all.
This study started when doctors in the reproductive endocrine unit at Massachusetts General Hospital carried out tests on a family from Saudi Arabia.
A number of individuals in this family, both male and female, had failed to go through puberty. The scientists analysed blood taken from each member of the family.
They found that the gene that codes for GPR54 was mutated in all those who had failed to reach puberty. It was fine in those who did not have the condition.
At the same time, scientists at the UK biotechnology company Paradigm Therapeutics contacted the US doctors to tell them they had bred mice that had failed to reach puberty. They had "knocked out" the gene for GPR54 in these mice.
"It looks like we have found a key genetic gatekeeper of puberty in mice and men," said Dr William Crowley Jr, chief of the reproductive endocrine unit and one of those involved in the study.
The scientists believe the gene makes a protein that helps to release the hormones that are responsible for the physical changes around puberty.
Both groups of scientists believe drugs could be developed to ensure this gene works properly and children can go through puberty normally.
But they also believe it could help people with fertility problems and some types of cancer.
"These findings define a new drug target with wide potential for therapeutic intervention in conditions such as hormonal-dependent cancer, abnormal puberty and control of fertility," said Dr Samuel Aparicio of Paradigm Therapeutics.
About one in 10,000 fail to go through puberty. Many others go through puberty too, some at just two years old.
These hormonal changes can be disastrous when they strike a young child.
If left to proceed unchecked, it could mean that growth is stunted as the body receives chemical signals telling it to switch off further height gain.