Novel biallelic loss-of-function mutations in cause multiple morphological abnormalities of the sperm flagellum in Pakistani families.

Multiple morphological abnormalities of the sperm flagella (MMAF) is a specific type of asthenoteratozoospermia, presenting with multiple morphological anomalies in spermatozoa, such as absent, bent, coiled, short, or irregular caliber flagella. Previous genetic studies revealed pathogenic mutations in genes encoding cilia and flagella-associated proteins (CFAPs; e.g.