Parkin mutations are responsible for the pathogenesis of autosomal-recessive 
juvenile parkinsonism (AR-JP). On initial screening of Japanese patients with 
AR-JP, we had found that approximately half of the parkin mutations are 
deletions occurring between exons 2 and 5, forming a deletion hot spot. In this 
study, we investigated the deletion breakpoints of the parkin mutations in 22 
families with AR-JP and examined the possible association between these deletion 
events and meiotic recombinations. We identified 18 deletion breakpoints at the 
DNA nucleotide sequence level. Almost all these deletions were different, 
indicating that the deletion hot spot was generated by recurrent but independent 
events. We found no association between the deletions and specific DNA elements. 
Recent copy number variation (CNV) data from various ethnic groups showed that 
the deletion hot spot is overlapped by a highly polymorphic CNV region, 
indicating that the recurrent deletion mutation or CNV is observable worldwide. 
By comparing Marshfield and deCODE linkage maps, we found that the parkin 
deletion hot spot may be associated with a meiotic recombination hot spot, 
although such association was not found on comparison with recent 
high-resolution genetic maps generated from the International HapMap project. 
Here, we discuss the possible mechanisms for deletion hot spot formation and its 
effects on human genomes.