title: Analysis of polymorphisms in the SRD5A2 gene and semen parameters in Estonian men.
abstract: Spermatogenesis is an androgen-dependent process and polymorphisms in genes encoding androgen-metabolizing enzymes may be associated with impaired male fertility. The enzyme steroid 5α-reductase converts testosterone into dihydrotestosterone. We analyzed genotype frequencies of 5 single-nucleotide polymorphisms (SNPs 1-5) (rs632148, rs523349, rs2300701, rs2268797, and rs12470143) in the steroid 5α-reductase type 2 gene (SRD5A2) in 132 azoospermic or oligozoospermic and 211 normozoospermic men. We found no association between investigated genotypes and the occurrence of male infertility. Linear regression analysis revealed a significant correlation between certain alleles of SNP1 and SNP5 and testicular volume among control men. Normozoospermic men carrying the minor allele of all but SNP5 polymorphism exhibited a significantly higher proportion of progressively motile spermatozoa, compared with major homozygotes. However, SRD5A2 genotypes did not influence sperm concentration, serum testosterone, or follicle-stimulating hormone levels in controls. Our results suggest that polymorphisms examined in SRD5A2 exhibit no adverse effect on semen parameters in Estonian men.
authors.affiliation: Department of Obstetrics and Gynecology, University of Tartu, L. Puusepa 8, Tartu 51014, Estonia. mpeters@ebc.ee
authors.forename: Maire
authors.initials: M
authors.lastname: Peters
authors.forename: Merli
authors.initials: M
authors.lastname: Saare
authors.forename: Tanel
authors.initials: T
authors.lastname: Kaart
authors.forename: Kadri
authors.initials: K
authors.lastname: Haller-Kikkatalo
authors.forename: Ave Kris
authors.initials: AK
authors.lastname: Lend
authors.forename: Margus
authors.initials: M
authors.lastname: Punab
authors.forename: Andres
authors.initials: A
authors.lastname: Metspalu
authors.forename: Andres
authors.initials: A
authors.lastname: Salumets
mesh_terms: D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D053713:Azoospermia / Q000235:genetics*; D016022:Case-Control Studies; D004957:Estonia; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D009845:Oligospermia / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D055101:Semen Analysis; D055815:Young Adult
chemical_list: D008565:Membrane Proteins; D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase; C548468:SRD5A2 protein, human