Protocadherin Alpha Gene Polymorphisms in Bipolar Disorder. Results from the Czech Cohort

Abstract

Aims:

Protocadherins (PCHD) are cell adhesion proteins with an important role in neuronal migration, differentiation and synaptogenesis. The linkage studies suggest that the 5q31-linked protocadherin family locus should be considered as potential candidate locus in schizophrenia and bipolar disorder. In this study, we focused particularly on single-nucleotide polymorphisms (SNPs) located in PCHDα enhancer. Results from the Czech cohort of patients with bipolar disorder (BD) will be presented.

Methods:

Unrelated inpatients and outpatients with BD based on Schedule for Affective Disorders and Schizophrenia - Lifetime (n=167) and blood bank donors as control subjects (n=211) were recruited in the study. Four SNPs posted in dbSNP (rs31745, rs10036519, rs3756337 and rs59497) in the PCDHα gene enhancer were analyzed. The data sets were analysed using a case control design.

Results:

In case of SNP, rs31745, a significant increase in homozygosity for the minor allele (T) was detected in patients with BD; 5% had this genotype, but no controls (p=0.001). The distribution of allels did not differ between patients and controls. No significant differences were found in allele or genotype distribution for three other SNPs.

Conclusions:

The findings suggest that the PCHDα is an interesting gene family to consider in BD susceptibility.