Basal ganglia disease- biotin-responsive
Overview
Biotin-responsive basal ganglia disease (BBGD) is a recessive disorder with childhood onset that presents as a subacute encephalopathy, with confusion, dysarthria, and dysphagia, and that progresses to severe cogwheel rigidity, dystonia, quadriparesis, and eventual death, if left untreated
Symptoms
* Confusion * Dysarthria * Dysphagia * Occasional supranuclear facial nerve palsy * External ophthalmoplegia
Diagnosis
All patients diagnosed to date are of Saudi, Syrian, or Yemeni ancestry, and all have consanguineous parents. Using linkage analysis in four families, we mapped the genetic defect near marker D2S2158 in 2q36.3 (LOD=5.9; theta=0.0) to a minimum candidate region (approximately 2 Mb) between D2S2354 and D2S1256, on the basis of complete homozygosity.