Species: human
Mutation name: None
type: naturally occurring
fertility: subfertile
Comment: Imperato-McGinley et al. (1974) studied 12 families with 22 male pseudohermaphrodites. The affected males are born with ambiguous genitalia and masculinize at puberty without breast development. The testes are normal histologically. The patients have no mullerian structures, complete wolffian differentiation, small phallus, bifid scrotum, urogenital sinus with perineal hypospadias and blind vaginal pouch. At puberty, they show male habitus with excellent muscular development, voice change, enlargement of phallus and production of semen, but small prostate and scanty beard. Plasma testosterone is normal; plasma 5-alpha-dihydrotestosterone is low. An abnormally small amount of radioactive testosterone is converted to dihydrotestosterone. One woman studied showed the same biochemical defect.

Species: human
Mutation name:
type: naturally occurring
fertility: subfertile
Comment: Association of genetic variants in the two isoforms of 5α-reductase, SRD5A1 and SRD5A2, in lean patients with polycystic ovary syndrome. Graupp M et al. (2011) Given its role in converting testosterone to dihydrotestosterone and cortisol to dihydrocortisol, 5α-reductase may be important in the pathophysiology of the polycystic ovary syndrome (PCOS). Increased activity of this enzyme has already been demonstrated in ovaries of affected women, and might be caused by genetic alterations. The aim of this study was to analyze representative genetic variants of both isoforms of 5α-reductase with regard to PCOS parameters in lean and obese women. We analyzed one single nucleotide polymorphism (SNP) (rs523349) of the isoform 2 (SRD5A2) and one haplotype of the isoform 1 (SRD5A1), consisting of the two SNPs rs39848 and rs3797179, in 249 women with PCOS and 226 healthy women using a 5'-exonuclease-assay. The genotypes were associated with anthropometric, metabolic and hormonal as well as functional tests in these women. In the investigated haplotype of SRD5A1, the TA variant was associated with an increased frequency of PCOS (P=0.022) and an increased Ferriman-Gallwey Score (hirsutism) (P=0.016) in women with normal weight. The G allele at the examined position of the SRD5A2 showed a decreased frequency of PCOS (P=0.03) in women with normal weight. One of the keys in the development of the PCOS is hyperandrogenism, which might be caused by an increased 5α-reductase activity, as it is often seen in obesity. This mechanism might therefore be of importance in lean PCOS patients and contribute to the clinical findings.//////////////////

Species: human
Mutation name:
type: naturally occurring
fertility: subfertile
Comment: Variants in the 5-Alpha-Reductase Type 1 and Type 2 Genes Are Associated with Polycystic Ovary Syndrome and the Severity of Hirsutism in Affected Women. Goodarzi MO et al. Context: Despite the importance of dihydrotestosterone in androgen action, polymorphisms in the genes for the two isoforms of 5alpha-reductase (SRD5A1 and SRD5A2) have not been evaluated as risk factors for polycystic ovary syndrome (PCOS). Objective: The objective of the study was to test the hypothesis that haplotypes in the SRD5A1 and SRD5A2 genes are risk factors for PCOS and the severity of hirsutism in affected women. Design: PCOS and control subjects were genotyped for seven single nucleotide polymorphisms (SNPs) in SRD5A1 and eight SNPs in SRD5A2. Haplotypes were determined and tested for association with PCOS diagnosis and component phenotypes. Setting: Subjects were recruited from the reproductive endocrinology clinic at the University of Alabama at Birmingham; control subjects were recruited from the general surrounding community. Genotyping took place at Cedars-Sinai Medical Center in Los Angeles. Participants: 287 White women with PCOS and 187 controls. Main Measurements: SRD5A1 and SRD5A2 genotype, quantitative hirsutism score, hormonal and metabolic phenotypes. Results: Haplotypes within both genes were associated with PCOS risk. The Leu allele of the Val89Leu variant in SRD5A2 was associated with protection against PCOS; this allele is known to modestly reduce 5alpha-reductase activity. Haplotypes in SRD5A1 but not SRD5A2 were also associated with the degree of hirsutism in affected women. Conclusions: This study presents genetic evidence suggesting an important role of both isoforms of 5alpha-reductase in the pathogenesis of PCOS. That only SRD5A1 haplotypes were associated with hirsutism suggests that only this isoform is important in the hair follicle.

Species: ovine
Mutation name:
type: naturally occurring
fertility: fertile
Comment: Comparative analysis of ovarian transcriptomes between prolific and non-prolific goat breeds via high-throughput sequencing. Zi XD et al. (2017) To increase the current understanding of the gene expression in the pre-ovulatory ovary and identify the key genes involved in the regulation of ovulation rate, we compared the transcriptomes of ovaries from the prolific Jintang black goat (JTG) and the non-prolific Tibetan goat (TBG) during the follicular phase using the Illumina RNA-Seq method. Three ovarian libraries were constructed for each breed. On average, we obtained approximately 49.2 and 45.9 million reads for each individual ovary of TBGs and JTGs, respectively, of which 79.76% and 78.67% reads were covered in the genome database. A total of 407 differentially expressed genes (DEG) were detected between these two breeds, in which 316 were upregulated, and 91 were downregulated in the ovaries of JTGs versus TBGs. Based on the results of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, some of these DEGs potentially play an important role in controlling the development of ovarian follicles. SRD5A2, MSMB, STAR and 3BHSD, etc. were the most significantly differentially expressed between these two distinct breeds. In addition, each ovary expressed 1,066 versus 989 novel transcripts, and 171,829 versus 140,529 putative SNPs in TBGs versus JTBs, respectively. All data sets (GEO and dbSNP) were available via public repositories. Our study provides insight into the transcriptional regulation of the ovaries of two distinct breeds of goats that might serve as a key resource for understanding goat fecundity. SRD5A2, MSMB, STAR and 3BHSD may be associated with the high fecundity of JTGs.//////////////////