Assessment of Nurr1 nucleotide variations in familial Parkinson's disease.

Parkinson's disease (PD) is characterised by the death of dopaminergic neurons of the substantia nigra. As Nurr1 seems to regulate the development and maintenance of these neurons, we evaluated its potential role in Parkinson's disease using genetic methods. We genotyped two polymorphisms and screened a case-control sample for the presence/absence of two mutations recently described in exon 1. Our results failed to replicate the association initially observed and none of the mutations were present in our familial Parkinson's disease cases. These observations suggest that this gene is unlikely to play a major effect in French familial Parkinson disease.

Association of polymorphisms in the Tau and Saitohin genes with Parkinson's disease.

BACKGROUND: The Saitohin gene has recently been identified in intron 9 of the Tau gene. Because an association between Parkinson's disease and Tau has been described, Saitohin represents a candidate gene for Parkinson's disease. OBJECTIVE: To test these two genes for their association with Parkinson's disease in a large community based case-control study. RESULTS: Cases (n = 208) were more often homozygotes for the Tau H1 haplotype than controls (n = 483; odds ratio (OR) = 1.71 (95% confidence interval, 1.20 to 2.43); p = 0.003), and the saitohin Q allele was in complete linkage disequilibrium with the H1 haplotype. This association was stronger among cases with Parkinson's disease onset below 65 years (< or =65 years: OR = 2.52 (1.49 to 4.25); p<0.001) than among those with older onset (>65 years: OR = 1.20 (0.73 to 1.98); p<0.47). CONCLUSIONS: The data suggest that there is a functional polymorphism at this locus involved in Parkinson's disease.

No genetic association of the ubiquitin carboxy-terminal hydrolase-L1 gene S18Y polymorphism with familial Parkinson's disease.

Parkinson's disease (PD) is a neurodegenerative disorder for which genetic susceptibility has been documented in sporadic and familial cases. Recently, a polymorphism located in exon 3 at codon 18 (S18Y) of the Ubiquitin Carboxy-terminal Hydrolase-L1 (UCH-L1) gene has been associated with the disease in 2 populations of German origin and also in a Japanese population. We tested the impact of this polymorphism in a French sample of familial PD patients (n = 114) and controls (n = 93). No association was observed, indicating that this polymorphism did not confer susceptibility for familial PD in our population, even among the youngest age of onset group. This observation suggests that the previous positive results obtained may reflect mechanisms restricted to the sporadic form of the disease or to a founder effect of the disease susceptibility.

Genetic analysis of synphilin-1 in familial Parkinson's disease.

alpha-Synuclein is present in Lewy bodies of patients with both sporadic and familial Parkinson's disease. However, pathogenic mutations Ala30Pro and Ala53Thr in alpha-synuclein are rare causes of disease. Synphilin-1 has been demonstrated to associate with alpha-synuclein and promote the formation of cytosolic inclusions in vitro. Two-point genetic linkage analysis of a dinucleotide repeat within the synphilin-1 gene initially implicated this locus as a cause of Parkinson's disease in three of nine families. However, subsequent haplotype, sequencing, and association analyses in these three families and an independent case-control series suggest that variability within the locus does not confer susceptibility to Parkinson's disease.