Girls’ puberty age depends on the genes they inherit from their parents, new research suggests. The research was published on July 23 in the journal Nature.

The “imprinted” genes that influence the age at which girls’ sexual maturity peaks are a small subset of genes with varied activity depending on which parent the gene came from.

These findings are a result of an international study involving more than 180,000 women and scientists from 166 institutions around the world. The researchers identified 123 variations in genes that are linked with when a girl’s menstrual cycle begins by analyzing DNA from 182,416 women of European descent.

The study’s lead author, Dr. John Perry, from the Medical Research Council Epidemiology Unit at the University of Cambridge, said in a statement, “Normally, our 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. Our findings imply that in a family, one parent may more profoundly affect puberty timing in their daughters than the other parent.”

The study shows that some genes are only activated when inherited from the mother, while others are only activated when inherited by the father.

According to kidshealth.org, puberty typically begins between ages eight and 13 in girls and in boys between the ages of nine and 15.