Skip to
  1. Homepage
  2. Rare diseases
  3. Search
Simple search

Simple search

(*) mandatory field


Other search option(s)

Brachydactyly type B

Synonym(s) -
Prevalence <1 / 1 000 000
Inheritance Autosomal dominant
Age of onset Infancy
  • Q73.8
  • C1300267
MeSH -
MedDRA -


Disease definition

Brachydactyly type B (BDB) is a very rare congenital malformation characterized by hypoplasia or aplasia of the terminal parts of fingers 2 to 5, with complete absence of the fingernails.


Prevalence is unknown but only a few cases have been reported in the literature.

Clinical description

The thumbs are always intact but frequently show flattening, splitting or duplication of the distal phalanges. Digits on the radial side of the hand are less severely affected than those on the ulnar side. The feet are similarly affected but less severely. Soft tissue syndactyly, symphalangism, carpal and/or tarsal fusions and shortening of metacarpals and/or metatarsals may be present.


In the majority of cases, BDB is caused by mutations in the receptor kinase-like orphan receptor 2 gene (ROR2) on 9q22.

Genetic counseling

An autosomal dominant pattern of inheritance has been reported.

(*) Required fields.

Attention: Only comments seeking to improve the quality and accuracy of information on the Orphanet website are accepted. For all other comments, please send your remarks via contact us. Only comments written in English can be processed.

Captcha image

Detailed information

Review article
Get Acrobat Reader
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.