Functional evidence implicating NOTCH2 missense mutations in primary ovarian insufficiency etiology

Area of Science:

• Genetics
• Endocrinology
• Reproductive Biology

Background:

• Primary ovarian insufficiency (POI) affects women under 40, impacting fertility and health.
• Whole exome sequencing (WES) has identified NOTCH2 gene mutations in some POI patients.
• The functional consequences of these NOTCH2 mutations in POI remain largely unexplored.

Purpose of the Study:

• To investigate the functional impact of NOTCH2 mutations identified in women with primary ovarian insufficiency.
• To assess the role of NOTCH2 mutations in the etiology of POI.
• To establish genotype-phenotype correlations for NOTCH2 mutations in POI.

Main Methods:

• Reanalysis of whole exome sequencing (WES) data from POI patients.
• Utilized a KGN granulosa-like cell model.
• Employed a synthetic gene reporter construct with luciferase gene expression to evaluate transcriptional activity of NOTCH2 mutations.

Main Results:

• Three specific NOTCH2 mutations (p.Ser1804Leu, p.Ala2316Val, and p.Pro2359Ala) demonstrated a functional impact on the protein's transcriptional activity.
• These findings provide the first evidence linking NOTCH2 mutations to the development of primary ovarian insufficiency.
• The study highlights the potential for ovarian dysfunction in Alagille syndrome patients with NOTCH2 mutations.

Conclusions:

• NOTCH2 mutations are implicated in the etiology of primary ovarian insufficiency.
• Sequencing the NOTCH2 open reading frame is recommended for large cohorts of POI patients to establish genotype-phenotype correlations.
• Further investigation is warranted regarding ovarian dysfunction in Alagille syndrome patients carrying NOTCH2 mutations.