Linkage analysis of juvenile parkinsonism to tyrosine hydroxylase gene locus on chromosome 11.

We performed linkage analyses of juvenile parkinsonism with autosomal recessive inheritance (AR-JP) to chromosome 11p15.5 locus including tyrosine hydroxylase (TH), Harvey-ras-1 (HRAS), and insulin (INS) genes by analyzing genomic DNA from 28 members of seven Japanese AR-JP families containing 10 affected individuals. We used the methods of pairwise linkage analysis (LIPED) and multipoint linkage analysis (LINKAGE) for genetic linkage to the chromosome 11p15.5 markers and detected recombination events between AR-JP locus and TH gene. Multipoint linkage analysis excluded the linkage in the interval between TH and HRAS, as well as 11 cMo distal to TH and 8.5 cMo distal to HRAS, a total of approximately 23 cMo on chromosome 11p.