CATSPER2 encodes the pore-forming subunit of the CatSper complex, a sperm-specific voltage-gated calcium channel essential for male fertility 1. The channel functions as a polymodal chemosensory calcium channel that orchestrates critical physiological events required for successful fertilization, including sperm hyperactivation, capacitation, acrosome reaction, and chemotaxis toward the oocyte 1. CATSPER2 expression is restricted to spermatozoa, with protein localization in the sperm principal piece 1. CATSPER2 mutations and deletions directly impair male fertility through loss of sperm motility and function. Homozygous CATSPER2 deletions cause asthenoteratozoospermia (abnormal sperm morphology and motility), representing the first human autosomal gene defect associated with nonsyndromic male infertility 2. Deletions spanning the STRC-CATSPER2 region on chromosome 15.3 cause deafness-infertility syndrome, combining hearing loss with male infertility due to impaired sperm motility 34. Recent molecular studies identified missense variants in CATSPER2 in unexplained infertility patients 5, and demonstrated that cryopreservation reduces CATSPER2 expression and protein levels, correlating with sperm motility loss 6. Hormonal interventions (HCG) can upregulate CATSPER2 expression and improve sperm quality 7, suggesting therapeutic potential for male infertility management.