Synaptotagmin XI in Parkinson's disease: New evidence from an association study in Spain and Mexico.

Introduction: The pathophysiology of PD (Parkinson's disease) has been related to the ubiquitin proteasome system and oxidative stress. Parkin acts as ubiquitin ligase on several substrates. Because genetic variants often have different frequencies across populations, population specific analyses are necessary to complement and validate results from genome-wide association studies.

mtDNA nt13708A variant increases the risk of multiple sclerosis.

Background: Mitochondrial DNA (mtDNA) polymorphism is a possible factor contributing to the maternal parent-of-origin effect in multiple sclerosis (MS) susceptibility.

Methods And Findings: In order to investigate the role of mtDNA variations in MS, we investigated six European MS case-control cohorts comprising >5,000 individuals. Three well matched cohorts were genotyped with seven common, potentially functional mtDNA single nucleotide polymorphisms (SNPs).