A form of brachydactyly (OMIM:112600) characterised by shortening of the middle phalanges of the index finger and second toe (the other digits are relatively normal). The rhomboid or triangular shape of the affected middle phalanx usually results in radial deviation of the end of the second finger.
Molecular pathology Defects of:
• BMP2, which encodes a protein belonging to the transforming growth factor-beta superfamily that induces bone and cartilage formation.
• BMPR1B, which encodes a member of the type I bone morphogenetic protein–BMP receptor family of transmembrane serine/threonine kinases that bind BMPs and play a central role in endochondral bone formation and embryogenesis.
• GDF5, which encodes a protein thought to be involved in bone and cartilage formation,
cause brachydactyly A2.
Synonyms Brachydactyly—Mohr-Wriedt type, brachymesophalangy II, Mohr-Wriedt type brachydactyly