Angel shaped phalangeal dysplasia, hip dysplasia, and positional teeth abnormalities are part of the brachydactyly C spectrum associated with CDMP-1 mutations.

I n 1967, Bachman described a ‘‘hereditary peripheral dysostosis’’ which affected a mother and her two children. What was later considered as multiple epiphyseal dysplasia combined with phalangeal cone shaped epiphyses was renamed angel shaped phalangoepiphyseal dysplasia (ASPED) and considered as a genetic bone marker. ASPED represents a further variety of multiple epiphyseal dysplasia and is transmitted as an autosomal dominant trait. It is radiologically diagnosed by the characteristic angel shape of the middle phalanges, typical metacarpophalangeal pattern profile, and epiphyseal changes in the hips. The angel shape of the middle phalanges is an isolated bone variation, similar to the non-syndromal, cone shaped epiphyses of type 12. Clinical manifestations in ASPED are not restricted to the hands, and the original paper reported on various combinations of angel shaped phalanges, hip dysplasia, and hypodontia. Patients range in stature from short to normal. Osteoarthritis of the hips can be significant, with severe intermittent hip pain. Hyperextensible interphalangeal joints of the fingers have been documented, as well as retarded bone age. Late eruption of deciduous teeth or persistent primary lower incisors have been described. Hypodontia was noted in four out of seven patients in Giedion’s cohort, and in 1.6 to 9.6% in the general population. Brachydactyly type C (BDC) is characterised by shortening of the first metacarpal and of the second, third, and fifth middle phalanges. Other common hand findings include ulnar deviation of the index finger and polyphalangy. Several reports on BDC emphasise variability of findings such as talipes, shortening of the middle phalanges of the toes, hip dysplasia, and short stature, but have not emphasised the presence of hypodontia or angel shaped epiphyses. 7 CDMP-1 (also known as GDF5) is a secreted signalling molecule that participates in skeletal morphogenesis. CDMP-1 has been detected in the rat dental pulp, and could intervene in tooth development and maintenance. Heterozygous mutations in CDMP-1 occur in individuals with autosomal dominant BDC. We report on ASPED in a family with three affected members. Since types of ASP distinct from those observed in ASPED have been reported in BDC, and since short first metacarpal and hip dysplasia are common in both ASPED and BDC, we performed molecular biological testing and identified a known CDPM-1 mutation. We also report three affected individuals from another family with autosomal dominant BDC secondary to a new CDMP-1 mutation, associated with premature loss of teeth and hip dysplasia.