Phenotypic Variability of Alström’s Syndrome in Bedouin Sibs

A Bedouin brother and sister diagnosed with Alström’s syndrome phenotype (MIM 203800) are presented in this report. In addition to the classical criteria of the disease (obesity, diabetes mellitus, early loss of central vision, retinitis pigmentosa and sensorineural deafness), the elder sister showed recurrent attacks of focal dystonia mainly affecting the lower limbs. Variability of expression of the Alström syndrome gene in the diseased sibs is demonstrated by the presence of chronic hepatic disease in the girl against the presence of renal calculi and salt wasting nephropathy in her brother. The association between focal dystonia and Alström’s syndrome has not been previously reported. Although it is tempting to speculate that the described dystonia was part of Alström’s syndrome spectrum, a coincidental association cannot be eliminated.