Genetically caused non-syndromal nail abnormalities

The term "Nail disorder, nonsyndromic congenital" (NDNC) is used to describe a heterogeneous group of hereditary, dominant or recessive inherited, non-syndromic (isolated) nail anomalies, including the complete absence of the nail plate (Autosomal recessive congenital anonychia - OMIM 206800). Besides anonychia, hereditary forms of trachyonychia, koilonychia, leukonychia, watch glass nails, tubular nails, onychogrypose and pterygium inversusm unguis are described. The nail anomalies may affect 1 or more nails and may be associated with skeletal dysplasia. The group of NDCNs includes 10 clinical pictures NDCN1-NCDN10) (Khan S et al. 2015).

1. Nail disorder, nonsyndromic congenital 1, NDNC1(Twenty-nail-dystrophy; Onychodystrophy totalis, isolated)
2. Nail disorder, nonsyndromic congenital 2; NDNC2(Hereditary Koilonychia; Koilonychia hereditaria)
3. Nail disorder, nonsyndromic congenital 3; NDNC3(Leukonychia totalis/partialis)
4. Nail disorder, nonsyndromic congenital, 4; NDNC4;(Anonychia/Hyponychia congenita, Anonychia totalis)
5. Nail disorder, nonsyndromic congenital 5, NDNC5(Onycholysis partialis with scleronychia)
6. Nail disorder, nonsyndromic congenital 6, NDNC6(Anonychia/Hyponychia and Onychodystrophy)
7. Nail disorder, nonsyndromic congenital 7, NDNC7(Congenital isolated onychodysplasia)
8. Nail disorder, nonsyndromic congenital 8; NDNC8(isolated toenail dystrophy)
9. Nail disorder, nonsyndromic congenital 9; NDNC9(Isolated Anonychynycholysis)
10. Nail disorder, nonsyndromic congenital 10; NDNC10 (Claw-shaped nails; onychauxis)

1. Bergmann C et al (2006) Mutations in the gene encoding the Wnt-signaling component R-spondin 4 (RSPO4) cause autosomal recessive anonychia. On J Hum gene 79:1105-1109.
2. Khan S et al (2015) Genetics of human isolated hereditary nail disorders. Br J Dermatol 173:922-929.