Evaluation of genetic variations in exons 1-7 of SUN5 gene and its protein expression in men with acephalic spermatozoa referring to Royan Institute

Background: Acephalic spermatozoa syndrome is a one of the most severe forms of teratozoospermia which cause male infertility; it can be easily defined through detection of decapitated flagella, tailless sperm heads in the ejaculated. In this syndrome, the sperm s head is separated from the flagellum because there is a problem in head-tail junction. This condition was caused by a defect in the spermatogenesis stage in the testicle. It is an autosomal recessive type defect and probably has genetic implications in many cases. Furthermore, SUN5 (Sad1 and UNC84domain containing 5) produces a testis-specific protein that localized in the mature spermatozoa head-to-tail linkage site and plays a role in the attachment of the head-tail of the flagellum during spermatogenesis.Objective: In this study we investigated the variations of exons 1,2,3,4,5,6,7 of SUN5 gene and their related protein expression in infertile men with acephalic spermatozoa syndrome.Materials and Methods: In our study 20 infertile men with acephalic sperm syndrome and 30 normal fertile men as control groups were recruited. In order to do this study, we extracted DNA from peripheral blood using salting out method, designed primers and performed PCR reactions, after that Sanger-sequencing technique was done and results were analyzed by Finch TV. Furthermore, we also performed quantitative protein expression of SUN5 using Immunocytochemistry analysis for case and control groups.Results: Results of sanger-sequencing revealed no mutations or single nucleotide polymorphism (SNPs) between men with acephalic spermatozoa and control individual. We observed the expression of SUN5 protein at the linkage between head-tail, because we have not seen any mutation in these arise of the SUN5 gene, so we expected that no expression changes of protein have observed between case and control groups.Conclusion: Although the present study demonstrated that there is no relationship between the genetic variation of exons 1-7 SUN5 gene and acephalic spermatozoa syndrome, since SUN5 is necessary for head- tail junction, it seems for a closer look it should be suggested to examine other exons in this gene, introns, splice sites and the promoter.

کلیدواژه ها:

SUN5 gene ، Male infertility ، Acephalic spermatozoa syndrome