The effects and interactions of APOE and APH-1A polymorphisms in Alzheimer disease

Alzheimer disease (AD) is characterized by the accumulation of senile plaques composed of amyloid β-peptide, which is derived from β-amyloid precursor protein through degradation by β-secretase and y-secretase complexes. One of the major components of y-secretase complex, anterior pharynx-defective-1 (APH-1), is responsible for the activity of the γ-secretase complex. In this study, we searched for not only the most known common genetic risk factor, APOE, but also the APH-1a gene polymorphism in AD patients in a Turkish population.

In this study, 49 AD patients and 45 healthy controls were included. The genetic polymorphisms and allele frequencies of APOE and APH-1a were investigated. Patients were evaluated for behavioral, cognitive, and functional domains by detailed neurocognitive tests, and comparison between the above-mentioned polymorphisms and disease severity was made.

Although there was an increased tendency of the APO ε4 allele in the AD group, no statistically significant difference was detected either in APOE or APH-1a polymorphisms, not suggesting a strong susceptibility to the development of AD.

While searching for the pathogenesis of AD in order to develop novel diagnostic as well as therapeutic approaches, analysis of other genes with a possible role in AD is warranted.