Thus, we screened all the dementia genes in our cohort with a dementia family history and identified two known pathological mutations (PSEN1 p.L226R, PSEN2 p.H169N), one novel heterozygous missense mutation in the FTLD gene with AD phenotype (TBK1 p.D534H), and two likely benign MAPT (p.Q230R, p.V48L) variants in a Han Chinese AD cohort. The gene discussed is PSEN1; the disease is Alzheimer disease.