Two families with congenital nail anomalies: Nail formation in ectopic areas.

Two families with congenital nail anomalies are reported. The nail covered not only the dorsal but also some of the palmar aspect of the distal phalanx. The ungual phalanges of the affected fingers were lacking in the crescent-shaped cap and had a blunt Y-shaped bony projection. The anomalies may have been transmitted by an autosomal recessive gene.