Girls' puberty age depends on which parent's 'imprinted gene' they carry

A new study has found that the puberty age of girls largely depends on which of the two parents' 'imprinted' genes they have.

The findings come from an international study of more than 180,000 women involving scientists from 166 institutions worldwide, including the University of Cambridge. The researchers identified 123 genetic variations that were associated with the timing of when girls experienced their first menstrual cycle by analysing the DNA of 182,416 women of European descent from 57 studies. Six of these variants were found to be clustered within imprinted regions of the genome.

Lead author Dr John Perry from the University of Cambridge said that normally, the inherited physical characteristics reflect a roughly average combination of our parents' genomes, but imprinted genes place unequal weight on the influence of either the mother's or the father's genes, it was found that one parent may more profoundly affect puberty timing in their daughters than the other parent.

He added that they knew some imprinted genes controlled antenatal growth and development, but there was an increasing interest in the possibility that imprinted genes may also control childhood maturation and later life outcomes, including disease risks.

Senior author Dr Ken Ong said that they were also studying the genetic factors to understand how early puberty in girls is linked to higher risks of developing diabetes, heart disease and breast cancer in later life, and to hopefully one day break this link.

The research is published in the journal Nature.