Ujike, H., M. Yamamoto, et al. (2001). "Prevalence of homozygous deletions of the parkin gene in a cohort of patients with sporadic and familial Parkinson's disease." Mov Disord 16(1): 111-3.
Mutation of the parkin gene is a cause of familial Parkinson's disease of the autosomal recessive form; however, its significance in all Parkinson's disease cases is unclear. Deletions in the parkin gene were found in only 2.2% of 184 Japanese patients with Parkinson's disease. However, deletions were present in 25.0% and 40.0% of the patients with juvenile-onset (< 40 y) and with familiality, respectively. On the other hand, deletions were not found in any adult-onset cases (> 40 y). Half of the patients with parkin gene-related Parkinson's disease lacked both heredity and consanguinity.