Pathogenic missense variation in PABPC1L/EPAB causes female infertility due to oocyte maturation arrest at the germinal vesicle stage.

Women undergoing controlled ovarian hyperstimulation prior to in vitro fertilization (IVF) are treated using various protocols to induce multiple follicular growths. Complete failure of all oocytes to mature during IVF cycles is rare; however, it is a known cause of primary female infertility. Recently, pathogenic variations in a few genes have been identified in women with oocyte maturation defects; however, the underlying genetic causes remain largely unknown.This study included a Turkish family comprising three sisters with recurring oocyte maturation arrest at the germinal vesicle stage after multiple ovarian stimulations. Exome sequencing revealed a homozygous missense variant (c.1037C>T, p.Ala346Val) in the EPAB gene (also known as PABPC1L) in all three affected sisters, which was either absent or heterozygous in the unaffected family members. Functional experiments confirming the pathogenicity of the variant were performed by transfecting HEK293T cells and demonstrated the instability and increased rate of proteolysis of the mutated PABPC1L/EPAB protein. The identified variant, located in the well-conserved fourth RNA recognition motif (RRM4), in silico 3D modelling suggested changes in the physical properties of the pathogenic variant of PABPC1L/EPAB. Our findings validate PABPC1L/EPAB as an essential genetic contributor to the oocyte maturation process in humans and have direct implications for the genetic counselling of patients and their family members.

Analysis of transforming growth factor beta 1 (TGF-beta1) gene polymorphisms in Turkish patients with scleroderma.

Systemic sclerosis (SSc) is an autoimmune disease characterized by inflammation and fibrosis of the skin and visceral organs. Fibrosis associated with SSc is characterized by an increased synthesis of a wide range of extracellular matrix (ECM). TGF-beta is a pluripotent cytokine in a wide range of cell types. In particular it has been found to be a potent inducer of ECM protein synthesis and fibroblast migration. The TGF-beta1 gene is highly polymorphic and two signal sequence polymorphisms at codon 10 and codon 25 are linked to disease outcomes. In this study, we analysed two polymorphic sites of the TGF-beta1 gene, codon 10 and codon 25, in 43 Turkish SSc female patients with interstitial lung involvement and in 75 healty individuals by ARMS-PCR. In our study no significant difference was found in codon 10, codon 25 genotype frequencies between patient with SSc and the control group (p = 0.676, 0.375, respectively). Our findings suggest that codon 10 and 25 polymorphism cannot be related with SSc for Turkish population.