Sydney Brenner CH FRS FMedSci (born 13 January 1927) is a South African biologist and a 2002 Nobel prize in Physiology or Medicine laureate, shared with Bob Horvitz and John Sulston. Brenner made significant contributions to work on the genetic code, and other areas of molecular biology while working in the Medical Research Council (MRC) Laboratory of Molecular Biology in Cambridge, England. He established the roundworm Caenorhabditis elegans as a model organism for the investigation of developmental biology, and founded the Molecular Sciences Institute in Berkeley, California, U.S..
Brenner was born in the town of Germiston, Gauteng, South Africa. His parents, Lena (née Blecher) and Morris Brenner, were Jewish immigrants. His father, a cobbler, came to South Africa from Lithuania in 1910, and his mother from Riga, Latvia, in 1922. He has one sibling, a sister, Phyllis.