[Pathogenicity analysis of a novel PADI6 gene variant associated with female infertility]

To investigate the clinical phenotype and genetic characteristics of an infertile woman carrying a novel PADI6 gene variant.

An infertile woman who visited the Medical Genetics Center of Henan Provincial People's Hospital on April 29, 2024 was selected as the study subject. Clinical data of the proband and her family members were collected. Peripheral blood samples were obtained from the proband and her husband for genomic DNA extraction. Whole-exome sequencing (WES) was performed. Candidate variant was verified among the family members by Sanger sequencing. The pathogenicity of candidate variant was classified according to the American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines for the Interpretation of Sequence Variants. Relevant literature on the pathogenic variants of the PADI6 gene was reviewed for genotype-phenotype correlation analysis. This study was approved by the Medical Ethics Committee of Henan Provincial People's Hospital (Ethics No.: 2021-171).

The proband was a 35-year-old woman who underwent two oocyte retrieval cycles, yielding a total of five oocytes, with all embryos arrested at day 3 post-fertilization. WES identified a homozygous PADI6 variant, c.367+4_367+7del. In vitro splicing assay confirmed that this variant can cause skipping of exon 3, leading to a frameshift and alterations in the protein structure or premature termination of translation. Literature review identified 12 relevant publications, and the PADI6 c.367+4_367+7del was determined to be a novel variant.

The homozygous PADI6 c.367+4_367+7del variant probably underlay the pathogenesis of infertility in the proband.