In a prospective British occupational cohort with 5-yearly clinical examinations (n = 230/5,749 South Asian/white participants, age 39–79 years at baseline), age-related trajectories of fasting glucose (FG) and 2 h post-load glucose (PLG), log-transformed fasting insulin (FINS) and 2 h post-load insulin (PLINS), HOMA insulin sensitivity (HOMA2-%S) and HOMA insulin secretion (HOMA2-%B) were fitted for South Asian and white individuals who remained free of diabetes between 1991 and 2009. The gene discussed is INS; the disease is diabetes mellitus.