In developing humans and other mammals, not all genes are created equal – or equally used. The expression of certain genes, known as imprinted genes, is determined by just one copy of the parents’ genetic contribution. In humans, there are at least 80 known imprinted genes. If a copy of an imprinted gene fails to function correctly – or if both copies are expressed – the result can be a variety of heritable conditions, such as Prader-Willi and Angelman syndromes, or increased risk for cancer. Continue reading
