The oligoasthenoteratozoospermia group revealed an increase in CatSper1, Castper4, Hv1 and KCNu1 gen expressions higher (p<0.001 for all genes), no difference in gene expressions of CatSper2 and KCNU1 and a decrease in CatSper3 gene expression. The gene discussed is CATSPER2; the disease is oligoasthenoteratozoospermia.