Genomic imprinting

Genomic imprinting is an epigenetic phenomenon in which the expression of a gene depends on whether it was inherited from the mother or the father. Imprinted genes carry parent‑of‑origin marks, typically established in the germline and maintained in somatic cells by DNA methylation and histone modifications.

Key points:

• Imprinted genes are important for foetal growth, brain development and metabolism.
• Disruption of imprinting causes human disorders such as Prader–Willi syndrome, Angelman syndrome and Beckwith–Wiedemann syndrome.
• Imprinting is one mechanism that can contribute to sex differences in gene expression and disease risk.

See also: Epigenetics, DNA methylation.