Marcus Edred Pembrey FMedSci (born 20 April 1943) is a British clinical geneticist with a research interest in non-Mendelian inheritance in humans.

Born into a medical family, Marcus Pembrey spent his childhood in Hurstpierpoint, Sussex, where his father was a General Practitioner.

He was instrumental in ensuring that the design of the Avon Longitudinal Study of Parents and Children ALSPAC included a genetic component.

Following Swedish studies demonstrating transgenerational effects of food supply, Pembrey collaborated with Lars Olov Bygren on research that featured in a 2005 'Horizon' program on BBC television called 'the Ghost in Your Genes'.,.

[6][7] The focus of his current research is environmental epigenomics and transgenerational responses, and he writes, speaks and broadcasts widely on this area for both expert and lay audiences.