Parent-of-origin effects

Parent-of-origin effects refer to situations where the influence of a gene on an individual's traits depends on whether the gene was inherited from the mother or the father. In some cases, the same gene can have different effects depending on which parent passed it on. This occurs because certain genes are subject to "imprinting," where chemical modifications turn off one copy of the gene depending on its parental origin. These effects are important for development and can influence disease risk, making parentage a key factor in understanding genetics beyond just the genes themselves.