TSSK2 and male infertility: Testis-specific serine kinase 2 (TSSK 1,2) (TSSK1–log2 fold change-2.5187; p-value = 7.57E-05, TSSK2 – log2 fold-2.9543; p-value = 3.28E-05) are testis-specific kinases localized in spermatids and spermatozoa and deletion of Tssk1 and 2 causes male infertility due to haploinsufficiency (Xu et al., 2008), TSSKs have a crucial role in germ cell differentiation and sperm function (Salicioni et al., 2020).