mutation analysis of tnp1 gene in infertile men with varicocele

background: varicocele is associated with the failure of ipsilateral testicular growth and development, and the symptoms of pain and reduced fertility. the highly condensed structure of the sperm nuclear chromatin is provided by proper expression of transition nuclear protein (tnp) genes, so any dysregulational expression of these genes results in abnormal spermatogenesis and infertility. objective:  the aim of present study was to assess the association between tnp1 mutations and varicocele in iranian infertile men. materials and methods:  analysis of association between tnp1 gene mutation and varicocele phenotype was performed using pcr and single-stranded conformational polymorphism technique and dna sequencing in 82 varicocele infertile men and 80 control subjects. results:  sequence analysis was identified one variant in this gene that found in 15 infertile men and was absent in control group. this variant was a single nucleotide polymorphism that were identified in the intron region of this gene at position g.ivs1+75t>c. conclusion:  the effect of this nucleotide substitution in intronic region of the tnp1 gene and their role on expression remains to be determined