Insulin-like growth factor 1 (IGF1) polymorphism is associated with Alzheimer's disease in Han Chinese

► IGF1 rs972936 polymorphism was associated with LOAD risk in Han Chinese. ► T allele of rs972936 was a risk factor of LOAD. ► After stratification by ApoE ɛ4, the association is confined to non-ApoE ɛ4 carriers. ► Multivariate analysis also conferred this positive association.