World's oldest tortoise Jonathan, 194, has the genes of a five-year-old and could hold the key to slowing human ageing

From the Newshound archive · first published 8 October 2026.

Cambridge scientists have found that Jonathan, the 194-year-old Aldabra giant tortoise living on St Helena, carries 287 unique gene variants that appear to be driving his extraordinary lifespan. Dr Justin Gerlach at Peterhouse says Jonathan is not just coping better with ageing — he is genuinely ageing more slowly, with gene regulators that have remained unusually stable across almost two centuries of life.

Jonathan hatched in 1832, during the reign of King William IV, outliving his species' average lifespan of around 80 years by over a century.

Researchers found his genes excel at DNA repair, keeping inflammation in check, managing insulin regulation and holding cancer at bay.

Scientists say understanding what keeps Jonathan's gene regulators so stable could one day allow doctors to slow human ageing itself.