Single Nucleotide Polymorphism Analysis of Protamine Genes in Infertile Men

Abstract

Background Single nucleotide polymorphism (SNPs) are considered as one of the underlying causes of male infertility. Proper sperm chromatin packaging which involves replacement of histones with protamines has profound effect on male fertility. Over 20 SNPs have been reported for the protamine 1 and 2. Materials and methods The aim of this study was to evaluate the frequency of two previously reported SNPs using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) approach in 35, 96 and 177 normal, oligozoospermic and azoospermic individuals. These SNPs are: 1. A base pair substitution (G) at position 197 instead of T in protamine type 1 Open reading frame (ORF) including untranslated region, which causes an Arg residue change to Ser residue in a highly conserved region. 2. cytidine nucleotide change to thymidine in position of 248 of protamine type 2 ORF which caused a nonsense point mutation. Results The two mentioned SNPs were not present in the studied population, thus concluding that these SNPs can not serves as molecular markers for male infertility diagnosis. Conclusion The results of our study reveal that in a selected Iranian population, the SNP G197T and C248T are completely absent and are not associated with male infertility and therefore these SNPs may not represent a molecular marker for genetic diagnosis of male infertility.

Keywords

• protamine
• single nucleotide polymorphism
• mutation
• infertility