CFTR and Infertility: Despite the high carrier rates, the frequencies of these CFTR variants in infertile men were found to be approximately two times higher compared with the healthy RUSeq cohort and population study of Petrova et al. (F508del: chi-squared = 9.5131, df = 1, p-value = 0.00204; CFTRdel2,3(21kb): chi-squared = 37.231, df = 1, p-value = 1.05×10−9) [11].