AMH mutations with reduced in vitro bioactivity are related to premature ovarian insufficiency

B Alvaro Mercadal1, R Imbert2, I Demeestere3

  • 1Research Laboratory on Human Reproduction, Faculté de Médecine, Université Libre de Bruxelles, Brussels, Belgium Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire (IRIBHM), Faculté de Médecine, Université Libre de Bruxelles, Brussels, Belgium Fertility Clinic, Department of Gynecology and Obstetrics, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium beatriz.alvaro@erasme.ulb.ac.be.

Abstract

Insights

Mutations in the anti-Müllerian hormone (AMH) gene were identified in women with idiopathic premature ovarian insufficiency (POI). These AMH variants showed significantly reduced bioactivity, suggesting a role in POI development.

Area of Science:

  • Reproductive Endocrinology
  • Genetics
  • Molecular Biology

Background:

  • Genetic factors contribute to 5-15% of idiopathic premature ovarian insufficiency (POI) cases.
  • Anti-Müllerian hormone (AMH) regulates primordial follicle recruitment; AMH deficiency leads to premature ovarian follicle depletion in mice.
  • The specific genetic underpinnings of POI remain incompletely understood, highlighting the need for further gene discovery.

Purpose of the Study:

  • To investigate the potential role of anti-Müllerian hormone (AMH) gene mutations in the etiology of idiopathic premature ovarian insufficiency (POI).
  • To functionally assess the bioactivity of identified AMH variants in a cellular model.

Main Methods:

  • Sequencing of the entire coding sequence and exon-intron junctions of the AMH gene in 55 POI patients and 197 controls.
  • In vitro bioactivity assay using recombinant wild-type (wt) and mutated AMH proteins stimulating AMH receptor type 2 (AMHR2) in HEK293 T cells.
  • Luciferase reporter assay to quantify AMHR2 signaling activity in response to AMH variants.

Main Results:

  • Three rare or novel missense variants (R444H, G264R, D288E) in the AMH gene were identified in the POI cohort.
  • The identified AMH variants (R444H, G264R, D288E) demonstrated drastically reduced bioactivity compared to wild-type AMH in vitro.
  • Familial segregation of the D288E variant was observed in a patient whose mother also experienced POI at a young age.

Conclusions:

  • Rare and novel missense variants in the AMH gene are associated with idiopathic premature ovarian insufficiency.
  • The reduced in vitro bioactivity of these AMH variants supports their contribution to the pathogenesis of POI.
  • These findings suggest that AMH gene mutations are a potential cause of POI and warrant further investigation.