As has been shown previously [7], ApoE4 was more common in clinically diagnosed FTD compared with healthy elderly controls; 221 patients (31.4%) and 105 controls (23.2%) were at least heterozygous for ApoE4 (chi-squared test, P = .003), carrying either one or two ApoE4 alleles. The gene discussed is APOE; the disease is frontotemporal dementia.