Endocrine Abstracts

Background: Premature ovarian insufficiency (POI) is an ovarian defect characterized from primary or secondaryamenorrhea, high levels of FSH (> 25 UI/l) and low levels of estrogen, which occurs before age 40.

Objective: The aim of the study was to evaluate the clinical features and genetic causes of a group of 68 patients with POI.

Methods: We performed anamnestic and clinical evaluation, hormonal and autoimmunity assessment, pelvic ultrasonography, bone densitometry (DXA) and genetic analysis in 68 women presenting with POI. Genetic analysis was performed for the research of FMR1 pre-mutation and mutations of genes involved in BMP-15 and GDF-9 folliculogenesis. DNA was extracted from peripheral white blood cells. All the exons of the BMP-15 and GDF-9 genes were amplified by polymerase chain reaction and subjected to direct sequencing. A novel heterozygous mutation in exon 2 of BMP-15 gene was identified in a patient. Functional studies were performed to assess the in vitro effect of the identified BMP-15 gene variant. For the functional study COV434 cells of ovarian granulosa were used, which consistently express BMP responsive element (BRE) by assay with luciferase.

Results: 63 patients presented secondary amenorrhea, 5 primary amenorrhea. Mean age of menopause was 28 years. 9 patients (13%) had a family history of POI, 28 patients (41%) had one or more autoimmune diseases associated with POI. Pelvic ultrasound revealed the absence of ovarian follicles in 19 patients. Bone densitometry appeared dramatically reduced in 2 women. In 5 patients (7%) FMR1 pre-mutation was detected. In 1 patient we identified a new pathogenetic mutation in heterozygosis c.406G> C (V136L) of BMP-15. We found no mutations in the GDF-9 gene. After transfection in COV434 BMP-15 cells mutated V136L has a significantly reduced activity both if transfected by itself and along with the wild type gene.

Conclusion: POI is a multifactorial pathology with general health implications on affected women. Autoimmunity, familiar and genetic causes represent the most common etiology. We identified FMR1 pre-mutation in 7% of the women and a new BMP-15 mutation responsible for the observed phenotype.