Haploinsufficiency of the ATP6V1B2, a subunit of V‐ATPases, underlies genetic disorders including Dominant deafness‐onychodystrophy (DDOD), deafness, onychodystrophy, osteodystrophy, mental retardation and seizures (DOORS), and Zimmermann‐Laband syndromes, all characterized by congenital hearing loss and onychodystrophy. The gene discussed is ATP6V1B2; the disease is deafness.