ABSTRACT
BACKGROUND AND PURPOSE: Calcium levels have been proposed to play an important role in the selective vulnerability of nigrostriatal dopaminergic neurons in Parkinson's disease (PD). Recently, an association was reported between the calcium buffer, calbindin (rs1805874) and risk of PD in a Japanese patient-control series. METHODS: We genotyped rs1805874 in four independent Caucasian patient-control series (1543 PD patients, 1771 controls). RESULTS: There was no evidence of an association between rs1805874 and disease risk in individual populations or in the combined series (odds ratio: 1.04, 95% CI: 0.82-1.31, P = 0.74). DISCUSSION: Our study shows there is no association between rs1805874 and risk for PD in four Caucasian populations. This suggests the effect of calbindin on PD risk displays population specificity.
Subject(s)
Parkinson Disease/genetics , Polymorphism, Single Nucleotide , S100 Calcium Binding Protein G/genetics , Adult , Aged , Aged, 80 and over , Calbindin 1 , Calbindins , Case-Control Studies , Female , Gene Frequency , Genetic Association Studies , Genetic Predisposition to Disease , Humans , Ireland , Male , Middle Aged , Norway , Poland , Risk Factors , Sequence Analysis, DNA , United States , White People/geneticsABSTRACT
Parkin (PRKN) mutations are a common cause of early-onset parkinsonism, however the role of this gene in typical late-onset Parkinson's disease (PD) remains unresolved. A single nucleotide polymorphism in the promoter region (PRKN-258; rs9347683) has been observed to associate with PD, affect age-at-onset (AAO) of symptoms, and to functionally effect differential expression of the PRKN transcript. In the present study, PRKN-258 did not associate with PD, and no evidence for an AAO effect was observed in three age and gender-matched Caucasian patient-control series from Norway, Ireland and the US. These data do not support a role for this common variant in PD etiology.
Subject(s)
Genetic Predisposition to Disease , Parkinson Disease/genetics , Polymorphism, Genetic/physiology , Promoter Regions, Genetic/genetics , Risk , Ubiquitin-Protein Ligases/genetics , Adult , Aged , Aged, 80 and over , DNA Mutational Analysis , Female , Genotype , Humans , Ireland/epidemiology , Male , Middle Aged , Norway/epidemiology , Parkinson Disease/epidemiology , United States/epidemiologyABSTRACT
Eye movements during fixation were recorded in 55 normal subjects with ages ranging from 21 to 81 years. We analysed ocular fixation recordings using measurements of saccadic intrusion amplitudes and frequencies along with fixation periods and mean fixation displacement. Viewing conditions included monocular, binocular and presence or absence of a visual fixation target. Visual feedback reduced the saccadic intrusion amplitudes but had no effect on fixation periods or mean fixation displacements. Binocular viewing had no effect on saccadic intrusion amplitudes, fixation periods or mean fixation displacements. A decrease in fixation periods and an increase in the number of saccadic intrusions with age was observed. This approach could be a clinically useful tool to quantify ocular fixation in neurological disease.
Subject(s)
Fixation, Ocular/physiology , Saccades , Vision, Binocular/physiology , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Psychophysics , Vision Disorders/diagnosisABSTRACT
The role of genetics in parkinsonism has been confirmed over the last decade with the identification of genetic variation in seven genes, which are causative in familial forms of the disorder. A number of pathogenic mutations have been identified in the latest gene LRRK2, with a Gly2019Ser amino acid substitution identified in two siblings and one patient with idiopathic Parkinson's disease from Ireland. The clinical features resemble the idiopathic variant with a tremor predominant clinical picture shared by the siblings, slow progression of symptoms, and no observation of cognitive disturbance in all. The family and the sporadic individual were apparently not related and originated from different regions of Ireland, although haplotype analysis does suggest they share a common founder. The influence of the G2019S substitution on protein function and disease phenotype has yet to be fully resolved, but its elucidation will undoubtedly further our understanding of the mechanisms underlying Parkinson's disease.
