Age Factors, Age of Onset, Case-Control Studies, DNA Mutational Analysis, Family Health, Female, Genetic Predisposition to Disease, Genetic Testing, Genotype, Glycine, Humans, International Cooperation, Leucine-Rich Repeat Serine-Threonine Protein Kinase-2, Male, Parkinson Disease, Penetrance, Protein Serine-Threonine Kinases, Risk, Serine, Severity of Illness Index