Association of Two Polymorphisms in H2B.W Gene with Azoospermia and Severe Oligozoospermia in An Iranian Population

During spermatogenesis, the H2B family, member W (H2B.W) gene, encodes a testis specific histone that is co-localized with telomeric sequences and has the potential role to mediate the sperm-specific chromatin remodeling. Previously H2B.W genetic variants were reported to be involved in susceptibility to spermatogenesis impairment. In the present study, two single nucleotide polymorphisms (SNPs) in 5΄UTR and exon 1 of H2B.W gene were examined to investigate possible association of these polymorphisms with male infertility in Iranian population. This case control study was conducted in Royan institute during four-year period (2010–2013). Genetic alteration of two SNPs loci, −9C>T and 368A>G, in H2B.W gene were indicated in 92 infertile men who were divided into two main groups including azoospermia (n=46) and sever oligozoospermia (n=46), while there was 60 fertile men as control group. Azoosperima was also divided into three sub-groups including sertoli cell only syndrome (SCOS, n=21), complete maturation arrest (CMA, n=17) and hypo spermatogenesis (n=8) according to testicular biopsy. For analysis, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was applied. The frequency of allele −9T was significantly higher in CMA group than in patients with SCOS (P<0.05). The haplotype TA (corresponding to simultaneous occurrence of −9T and 368A) compared with haplotype CA (corresponding to simultaneous occurrence of −9C and 368A) in patients suffering from CMA significantly increased, compared with patients had SCOS (P<0.05). However, statistical studies indicated that in general, the distribution frequencies of −9C>T and 368A>G had no significant difference between the infertile groups and control (P=0.859 and P=0.812, respectively). This investigation showed that SNP −9C>T might be contribute to CMA in azoospermic patients and SNP 368A>G had no correlation with male infertility in Iranian population.