The relevance of ABCA1 R219K polymorphisms and serum ABCA1 protein concentration to Parkinson's disease pathogenesis and classification: a case-control study

To investigate the relevance of ABCA1 R219K polymorphisms and serum ABCA1 protein concentration to Parkinson's disease (PD) pathogenesis and classification in Chinese population. Between June 2013 to January 2014, 108 patients diagnosed with PD at Department of Neurology, Tangshan People's Hospital, Tangshan were enrolled in the PD group, and 123 healthy individuals, from Health Screening Center of the same hospital, with matched age, gender, and education were enrolled in the control group. Polymerase chain reaction-restriction fragment length polymorphism method was used to detect ABCA1 R219K polymorphisms and enzyme-linked immunosorbent assay used to measure serum ABCA1 concentrations. Frequencies of R/K and K/K genotypes, and K allele of ABCA1 R219K polymorphisms were significantly lower in the PD group than the control group (all P < 0.05). Significant differences existed in distributions of genotype frequencies, including R/R, R/K and K/K, between PD and control group of each classification (all P < 0.05). ABCA1 concentrations were significantly different in the PD and control group (P < 0.05); also ABCA1 concentrations were very different among PD patients with different genotypes (all P < 0.05). Serum concentrations of ABCA1were significantly different among PD patients in different classifications (all P < 0.05), suggesting the negative correlation between ABCA1 serum concentration and PD classification (r = -0.776, P < 0.05). And serum concentrations of ABCA1 showed obvious differences among cases with three different genotypes in each classification (all P < 0.05). ABCA1 R219K polymorphisms and serum concentration were associated with pathogenesis and classification of PD, and K allele may be a protective genetic factor.