ABSTRACT
BACKGROUND: Parkinson disease (PD) is a neurological disease responsible for a considerable rate of mortality and morbidity in the society. Since the symptoms of the disease appear much later than the actual onset of neuron degeneration, a majority of cases remain undiagnosed until the manifestation of the symptoms. OBJECTIVES: In order to investigate the existence of such susceptibility in the population, we analyzed Copy Number Variation (CNV) influences on PD genes in 1715 individuals from 12 different populations. RESULTS: Overall, 16 CNV-PD genes, 3 known to be causal and 13 associated, were found to be significantly enriched. PARK2, was under heavy burden with ~1% of the population containing CNV in the exonic region. The impact of these genes on the genome and disease pathway was analyzed using several genome analysis tools. Protein interaction network of CNV-PD genes revealed a complex interaction of molecules forming a major hub by the α-Synuclein, whose direct interactors, LRRK2, PARK2 and ATP13A2 are under CNV influence. CONCLUSIONS: We hypothesize that CNVs may not be the initiating event in the pathogenesis of PD and remain latent until additional secondary hits are acquired and also propose novel genes that may fall under the PD pathway which contribute in pathogenesis.
Subject(s)
DNA Copy Number Variations/genetics , Genetic Predisposition to Disease/genetics , Oligonucleotide Array Sequence Analysis , Parkinson Disease/ethnology , Parkinson Disease/genetics , Algorithms , Cohort Studies , Databases, Genetic , Female , Gene Expression Profiling , Gene Regulatory Networks , Genome-Wide Association Study , Genotype , Humans , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Male , Phenotype , Proton-Translocating ATPases/genetics , Ubiquitin-Protein Ligases/geneticsABSTRACT
MicroRNAs are involved in post-transcriptional down-regulation of gene expression. Variations in miRNA genes can severely affect downstream-regulated genes and their pathways. However, population-specific burden of CNVs on miRNA genes and the complexities created towards the phenotype is not known. From a total of 44109 CNVs investigated from 1715 individuals across 12 populations using high-throughput arrays, 4007 miRNA-CNVs (â¼ 9%) consisting 6542 (â¼ 5%) miRNA genes with a total of 333 (â¼ 5%) singleton miRNA genes were identified. We found miRNA-CNVs across the genomes of individuals showing multiple hits in many targets, co-regulated under the same pathway. This study proposes four mechanisms unraveling the many complexities in miRNA genes, targets and co-regulated miRNA genes towards establishment of phenotypic diversity.
