Familial pure paroxysmal kinesigenic dyskinesia in Han population from the Chinese mainland: A new subtype?

SummaryParoxysmal kinesigenic dyskinesia (PKD) is a rare neurologic inherited disease with heterogeneity. Autosomal dominant (AD) is the common inherited mode. There have been two loci mapped to 16 chromosome for PKD. However, no gene responsible for it has been identified so far. We collected 6 pedigrees from Chinese mainland. There were 122 members in all, including 26 affected. According to New diagnostic criteria of Bruno, they were diagnosed as pure PKD. From the clinic data, we found that the onset age was earlier and the severity was increasing in the subsequent generations in 4 pedigrees of them, which suggested genetic anticipation. Linkage analysis was applied in 2 of these pedigrees. The maximum LOD score and NPL score were negative. The followed haplotypes analysis excluded the PKD locus in both families from chromosome 16, providing evidence for a novel locus.