An international team has identified 30 new genes that could control the age of sexual maturation in women. Also several specific genetic links between early puberty and body fat have been discovered.
The study of more than 100,000 women from Europe, US and Australia found genes involved in hormone regulation, cell development and other mechanisms being linked to age at menarche (the onset of menstrual periods in women).
The results show that puberty timing is controlled by a complex range of biological processes and many of these genes also influence body weight regulation or fat metabolism.
Scientists from the Queensland Institute of Medical Research (QIMR) were part of the project.
According to Dr Enda Byrne, from QIMR's Queensland Statistical Genetics Laboratory, "Early puberty is a risk factor for a number of later life illnesses and poor health, including obesity and breast cancer."
"There has been a gradual decrease in the average age of menarche in the population over the last century which has been attributed to improved child nutrition. It has also been known for some time that higher weight gain in childhood is associated with earlier puberty."
"The results from this study show that many of the genes that increase risk for weight gain and obesity in adulthood, also influence timing of puberty. This supports the idea that the body launches into puberty once it reaches a certain level of nutrient stores and therefore children who are overweight are more likely to undergo early puberty."
"Our study identified genes involved in metabolism of fatty acids in the body as influencing timing of puberty. Some women inherit genes that make them more susceptible to weight gain and early puberty, but changes in lifestyle such as healthier eating and exercise can alter these genetic effects. One of the next stages of this study will be to test whether the same genes also influence timing of puberty in males."
The study was conducted by the large international ReproGen (Reproductive Genetics) consortium, with scientists from 104 worldwide institutions, including researchers at the Queensland Institute of Medical Research in Brisbane.
The study was supported in Australia by the Australian National Health and Medical Research Council and the Australian Research Council.