Brachymorphism-Onychodysplasia-Dysphalangism Syndrome

Clinical Features

Senior (1971) described 6 'short children with tiny fingernails.' Pre- and postnatal short stature, hypoplastic fifth digits with abnormal phalanges and tiny fingernails, facial dysmorphism, and, in some, mild intellectual impairment were observed. Mace and Gotlin (1973) reported a single case. As noted in connection with the Coffin-Siris syndrome (CSS; 135900), the condition reported by Senior (1971) resembles that disorder except that mental retardation is milder.

Verloes et al. (1993) reported 3 unrelated children with intrauterine proportionate growth retardation and facial dysmorphism (broad nose, flat malar area, large mouth, pointed chin), microcephaly, hypo/aplasia of the terminal fifth digits, and normal or only mildly reduced intelligence. Radiologic findings included hypo/aplasia or fusion of the distal phalanges of the fifth finger and toe, brachymesophalangism V, and nail dysplasia or aplasia. One of the 3 children had cystic adenomatoid disease of the lung. This disorder may be a mild form of Coffin-Siris syndrome or an independent entity. Verloes et al. (1993) suggested that it be called the brachymorphism-onychodysplasia-dysphalangism syndrome (BOD syndrome) because 'Senior syndrome' runs the risk of confusion with the Senior-Loken syndrome (266900).

Brautbar et al. (2009) described a 7-year-old girl with hypoplastic nails, especially on the fifth digit of each extremity, which were more noticeable on the feet, coarse face, broad nose, wide mouth, thick eyebrows, long eyelashes, accommodative esotropia, inguinal and umbilical hernia, large premium atrial septal defect and cleft mitral valve, hirsutism, and mild developmental delay. Brautbar et al. (2009) suggested that even though the patient met the minimal clinical diagnostic criteria of Coffin-Siris syndrome, some features, such as mild developmental delay and the more severe involvement of the feet when compared to the hands, are more consistent with BOD syndrome. Brautbar et al. (2009) suggested that CSS and BOD syndrome are probably allelic disorders.

Molecular Genetics

See 604958 for discussion of a possible association between variation in the ACTL6A gene and the disorder in the patient described by Brautbar et al. (2009).