No association of apolipoprotein epsilon 4 allele with schizophrenia even in cognitively impaired patients.

Abstract Given the strong association of the apolipoprotein E (apoE) allele epsilon 4 (ϵ4) with Alzheimer's disease or cognitive decline in elderly, we tested whether cognitive performance in schizophrenic subjects is associated with an increase in the frequency of the ApoE ϵ4 allele. Our data indicate that in our sample: (1) there is no association between schizophrenia and the ApoE ϵ4 allele; and (2) the ApoE ϵ4 allele is not of major importance with regard to the cognitive decline observed in schizophrenia.