PADI6 (peptidyl arginine deiminase 6) is a maternal-effect protein essential for early embryonic development that functions as a structural constituent of cytoplasmic lattices in oocytes and preimplantation embryos 1. Unlike other peptidyl arginine deiminases, PADI6 lacks catalytic deiminase activity due to its inability to bind calcium 23. Cytoplasmic lattices serve as critical storage structures for maternal proteins, including ribosomal proteins and factors controlling epigenetic reprogramming, preventing their premature degradation or activation 1. PADI6 is a component of the subcortical maternal complex (SCMC) and controls both nuclear and cytoplasmic oocyte maturation processes 4. It regulates zygotic genome activation, DNA demethylation, and histone H3.3 incorporation during preimplantation development 45. Mutations in PADI6 cause female infertility through early embryo arrest at the two-cell or preimplantation stages, often accompanied by defective oocyte maturation and impaired epigenetic reprogramming 64. PADI6 variants are also associated with multilocus imprinting disturbances 4. The gene exhibits tissue-restricted expression primarily in ovary and testis 7, and represents an important molecular marker for determining oocyte quality and predicting reproductive outcomes 8.