Benign hereditary chorea of early onset maps to chromosome 14q

Benign hereditary chorea (BHC) is an autosomal dominant disorder characteri zed by an early-onset nonprogressive chorea. The early onset and the benign course distinguishes BHC from the more common Huntington disease (HD). Pre vious studies on families with BHC have shown that BHC and HD are not allel ic. We studied a large Dutch kindred with BHC and obtained strong evidence for linkage between the disorder and markers on chromosome 14q (maximum LOD score 6.32 at recombination fraction 0). The BHC locus in this family was located between markers D14S49 and D14S1064, a region spanning similar to 2 0.6 cM that contains several interesting candidate genes involved in the de velopment and/or maintenance of the CNS: glia maturation factor-beta, GTP c yclohydrolase 1 and the survival of motor neurons (SMN)-interacting protein 1. The mapping of the BHC locus to 14q is a first step toward identificati on of the gene involved, which might, subsequently, shed light on the patho genesis of this and other choreatic disorders.