US sprinter Erriyon Knighton has been banned for four years after the Court of Arbitration for Sport (CAS) upheld appeals by World Athletics and the World Anti-Doping Agency (WADA) over his doping case.

Algerian boxer and Olympic champion Imane Khelif has filed an appeal with the Court of Arbitration for Sport (CAS) to contest the introduction of a gender test, according to a statement released by the court on Monday.

A Chinese research team has successfully completed the world's first transplant of a gene-edited pig liver into a brain-dead human, with the organ showing good physiological function.