Biemond syndrome type 2
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Assosciate Editor(s)-In-Chief: Prashanth Saddala M.B.B.S
Overview
A rare inherited condition characterized by mental retardation, obesity, polydactyly and underdeveloped genitals.
Pathophysiology
Genetics
Little is known about the inheritance or genetic defect responsible. Colobomas and polydactyly have been found in relatives of patients with Biemond syndrome suggesting that this may be an autosomal dominant disorder with variable penetrance.
Diagnosis
History and Symptoms
Ocular Features
This disorder may belong to the spectrum of Bardet-Biedl syndromes but is listed separately because of the prominent association of iris colobomata. Night blindness in the presence of retinal pigment degeneration. Retinal dystrophy resembling retinitis pigmentosa is also part of this disorder but the rarity of cases precludes a full description of the phenotype.
Systemic Features
- Underdevelopment of the external genitalia is more prominent in males.
- Obesity, hydrocephalus and mental retardation are also features.
- Postaxial polydactyly is common.
- Renal disease does not seem to be part of this disorder.
Treatment Options
None known.