Journal of Reproduction & Infertility

Journal of Reproduction & Infertility

Identification of Novel Nucleotide Changes in INHBB Gene by Mutation Screening in Females with Ovarian Dysgenesis: A Case Report

Authors
1 Centre for Genetic Disorders, Institute of Science, Banaras Hindu University, Varanasi, India
2 Department of Obstetrics and Gynaecology, Institute of Medical Science, Banaras Hindu University, Varanasi, India
Abstract
Background: Inhibin and activin regulate the follicle stimulating hormone level by their antagonistic actions and thus have been considered as strong candidate genes in the etiology of ovarian dysgenesis. In the present study, two cases of primary amenorrhea with poorly developed secondary sexual characteristics were reported. The purpose of the study was to identify mutations in candidate gene. Case Presentation: In this paper, clinical, genetic, biochemical, and molecular findings in female patients with primary amenorrhea were reported. Whole blood culture and G-banding for karyotyping, sequencing, and in silico analysis were performed following the standard protocol. Both cases were cytogenetically characterized as normal females with 46,XX, chromosome constitution. Hormonal assay revealed high level of follicle stimulating hormone and luteinizing hormone. DNA sequence analysis of inhibin identified two novel heterozygous missense mutations of c.975T>A and c.1156G>A which were translated into p.I310N and p.D386N, respectively. These identified positions were highly conserved across species during evolution. In silico prediction tools, intramolecular hydrogen bonding pattern and hydrophobicity analysis, revealed deleterious effect of p.I310N and neutral effect of p.D386N mutation. Conclusion: Our observation suggested that identified novel mutation in the first case might be the reason for ovarian dysgenesis and provides additional support to the previously reported genotype-phenotype correlations.
Keywords

  1. MacNaughton J, Banah M, McCloud P, Hee J, Burger H. Age related changes in follicle stimulating hormone, luteinizing hormone, oestradiol and immunoreactive inhibin in women of reproductive age. Clin Endocrinol (Oxf). 1998;36(4):339-45.
  2. Burger HG, Cahir N, Robertson DM, Groome NP, Dudley E, Green A, et al. Serum inhibins A and B fall differentially as FSH rises in perimenopausal women. Clin Endocrinol (Oxf). 1998;48(6):809-13.
  3. Reame NE, Wyman TL, Phillips DJ, de Kretser DM, Padmanabhan V. Net increase in stimulatory input resulting from a decrease in inhibin B and an increase in activin A may contribute in part to the rise in follicular phase follicle-stimulating hormone of aging cycling women. J Clin Endocrinol Metab. 1998;83(9):3302-7.
  4. Farnworth PG, Robertson DM, de Kretser DM, Burger HG. Effects of 31 kDa bovine inhibin on FSH and LH in rat pituitary cells in vitro: antagonism of gonadotrophin-releasing hormone agonists. J Endocrinol. 1988;119(2):233-41.
  5. Harris SE, Chand AL, Winship IM, Gersak K, Nishi Y, Yanase T, et al. INHA promoter polymorphisms are associated with premature ovarian failure. Mol Hum Reprod. 2005;11(11):779-84.
  6. Stenvers KL, Findlay JK. Inhibins: from reproductive hormones to tumor suppressors. Trends Endocrinol Metab. 2009;21(3):174-80.
  7. Cho BN, McMullen ML, Pei L, Yates CJ, Mayo KE. Reproductive deficiencies in transgenic mice expressing the rat inhibin alpha-subunit gene. Endocrinology. 2001;142(11):4994-5004.
  8. Shelling AN, Burton KA, Chand AL, Van Ee CC, France JT, Farquhar CM, et al. Inhibin: a candidate gene for premature ovarian failure. Hum Reprod. 2000;15(12):2644-9.
  9. Chand AL, Harrison CA, Shelling AN. Inhibin and premature ovarian failure. Hum Reprod Update. 2010;16(1):39-50.
  10. Dixit H, Rao KL, Padmalatha V, Kanakavalli M, Deenadayal M, Gupta N, et al. Expansion of the germline analysis for the INHA gene in Indian women with ovarian failure. Hum Reprod. 2006;21(6):1643-4.
  11. Prakash GJ, Ravi Kanth VV, Shelling AN, Rozati R, Sujatha M. Mutational analysis of inhibin alpha gene revealed three novel variations in Indian women with premature ovarian failure. Fertil Steril. 2010;94(1):90-8.
  12. Lopes AM, Aston KI, Thompson E, Carvalho F, Goncalves J, Huang N, et al. Human spermatogenic failure purges deleterious mutation load from the autosomes and both sex chromosomes, including the gene DMRT1. PLoS Genet. 2013;9(3):e1003349.
  13. Hagen CP, Main KM, Kjaergaard S, Juul A. FSH, LH, inhibin B and estradiol levels in Turner syndrome depend on age and karyotype: longitudinal study of 70 Turner girls with or without spontaneous puberty. Hum Reprod, 2010;25(12):3134-41.
  14. Gravholt CH, Naeraa RW, Andersson AM, Christiansen JS, Skakkebaek NE. Inhibin A and B in adolescents and young adults with Turner’s syndrome and no sign of spontaneous puberty. Hum Reprod. 2002;17(8):2049-53.
  15. Chand AL, Ooi GT, Harrison CA, Shelling AN, Robertson DM. Functional analysis of the human inhibin a subunit variant A257T and its potential role in premature ovarian failure. Hum Reprod. 2007;22(12):3241-8.
  16. Dixit H, Deendayal M, Singh L. Mutational analysis of the mature peptide region of inhibin genes in Indian women with ovarian failure. Hum Reprod. 2004;19(8):1760-4.
  17. Marozzi A, Porta C, Vegetti W, Crosignani PG, Tibiletti MG, Dalprà L, et al. Mutation analysis of the inhibin alpha gene in a cohort of Italian women affected by ovarian failure. Hum Reprod. 2002;17(7):1741-5.