Clinical relevance of tag single nucleotide polymorphisms within the CAT gene in patients with PTSD in the Chongqing Han population

Free radical-induced oxidative damage of the brain has been implicated in a number of psychiatric disorders, including post-traumatic stress disorder (PTSD). Catalase (CAT) is a major antioxidant enzyme and a number of polymorphisms in CAT have been shown to be associated with several diseases, including hypertension, diabetes mellitus, Alzheimer's disease, and vitiligo. The aim of this study was to evaluate the association of CAT gene polymorphisms with PTSD in a case-control study. A total of 460 unrelated adult Chinese Han adults, including 287 healthy volunteers and 173 patients with PTSD. Six tag single-nucleotide polymorphisms (tSNPs) were selected from the entire CAT gene through construction of haplotype bins, and they were genotyped using an improved multiplex ligation detection reaction (iMLDR) technique. Allelic frequencies and clinical characteristics were compared in two independent Chinese Han populations. Six tag SNPs were identified in the Chinese Han population and all were common SNPs. However, we could detect no evidence of genetic association between six tag SNPs in the CAT gene and PTSD in the Chinese Han population. This result suggests that six tag SNPs of the CAT gene may not be associated with PTSD, and that CAT gene might not influence the development of PTSD in patients following exposure to a traumatic event, also may be the sample sizes too small to allow a meaningful test.