Finally, it is noteworthy that the Apolipoprotein E (ApoE) genotype may be associated with the development of HHcy and that the Ɛ4 allele represents a risk factor for vascular contributions to cognitive impairment and dementia (VCID), and it is also considered to be the strongest genetic risk factor for late-onset AD [68]. The gene discussed is APOE; the disease is Alzheimer disease.