Does Apolipoprotein E polymorphism play a role in familial Alzheimer’s Dementia

AbstractBackgroundApo E4 is the best studied genetic risk factor for sporadic Alzheimer’s disease. Apo E2 homozygosity is associated with a lower risk of Alzheimer’s disease. While rare and common variants in genes encoding APP metabolism are strongly linked to familial dementia, however family history and ApoE 4 genetic risks have been found to co‐occur.Aim to evaluate the frequency of Apo E polymorphisms and their relationship with the of family history and clinical characteristics in a cohort of 483 patients with Alzheimer’s dementia.MethodPersons with Alzheimer’s dementia were identified from a tertiary care center in India. Their family history status, and detailed clinical characteristics were collected. Genotyping was done at the apolipoprotein E (Apo E) locus using real time PCR.ResultOf the 483 patients analyzed; 142 patients had a family history of Alzheimer’s dementia in at least one first degree relative. Absence of Apo E2 homozygosity was noted in the sample. Patients with family history had a higher likelihood of an Apo E4 carrier status (OR = 1.6071; Confidence Interval 1.0840 to 2.3829 p = 0.00182).The Apo E4 frequency in the overall sample was 25.05%.ConclusionThere is a correlation between Apo E4 carrier status and the likelihood of a positive family history. It remains to be known whether family history effects are separable from Apo E4 related effects.