Objective(s): Sperm-mediated oocyte activation depends upon suitable expression and assembly of sperm-borne oocyte-activating factors (SOAFs) during spermiogenesis. Several factors have been considered as candidates for oocyte activation in recent years. Globozoospermia is a severe sperm morphology disorder that is a rare type of teratozoospermia with an incidence of 0.1% among infertile individuals. testis-specific genes including CAPZA3 [capping protein (actin filament) muscle Z-line, alpha, which is considered as a nominee for sperm associated oocyte activating factors, an actin-capping protein, controlling actin polymerization during spermiogenesis. They contain a common bidirectional promoter. Another gene TR-KIT (a truncated form of the KIT receptor) which is a major sperm-associated oocyte-activating factor. The objective of this study was to investigate the expression profile of CAPZA3 and TR-KIT mRNA, in men with total globozoospermia, Asthenoteratospermia, and fertile individuals.
 Materials and Methods: Semen samples were collected from three groups including 25 fertile men, 20 Asthenoteratospermia and 12 Globozoospermia that undergo intra-cytoplasmic sperm injection (ICSI), Expression of CAPZA3 and TR-KIT were assessed by Real time PCR.
 Results: Individuals with Globozoospermia have presented significantly lower expression of CAPZA3 and TR-KIT mRNA when compared with fertile men. Asthenoteratospermia (male factor) showed significantly lower expression of CAPZA3 mRNA, whereas non-significantly of TR-KIT mRNA. Levels of CAPZA3 and TR-KIT mRNA in the spermatozoa of fertile men were significantly higher than the corresponding values of the globozoospermic and Asthenoteratospermia subjects.
 Conclusion: Analysis mRNA of CAPZA3 gene maybe assist the researcher to identify individuals with a lack of ability to induce oocyte activation and make them a candidate for artificial oocyte activation and help researcher to identify genetic defects associated with failed fertilization. whereas, mRNA of TR-KIT gene appears inability to induce oocyte activation
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