Parkinson's disease (PD) is the second most common neurodegenerative disorders throughout the world. In order to search for PD biomarkers, we performed a system-level study of RNA-Seq data from PD brain and blood samples. Differentially expressed miRs of RNA-Seq data were subjected to generate the Co expression networks. Three highly co-expressed clusters were identified based on their correlation coefficient values and fold change ratio. SM2miR drugs of the miRs contained in the three highly co expressed clusters were identified, and drugs common among these clusters were selected. Co expressed miRs not previously known to be associated with PD were identified from both the samples. Functional enrichment analyses of these miR targets were done, and the pathways common and unique to both the samples were identified. Thus, our study presents a comparative analysis of miRs, their associated pathways, and drugs from brain and blood samples of PD that may help in system level understanding of this disease. miRs identified from our study may serve as biomarkers for PD. (C) 2017 Elsevier Inc. All rights reserved.