JOURNAL OF PURE & APPLIED MICROBIOLOGY, Nov. 2014. Vol. 8(Spl. Edn. 2), p. 823-826 * To whom all correspondence should be addressed. E-mail: danielalexanand@gmail.com Computational Analysis of Micro RNA based Target Interactions Related to Genome Wide Association Studies of Psoriasis Harishchander Anandaram 1 and Daniel Alex Anand 2 * 1 Department of Bioinformatics, Sathyabama University, Chennai, India 2 Department of Biomedical Engineering, Sathyabama University, Chennai, India. (Received: 06 September 2014; accepted: 13 October 2014) Identification of a micro RNA (miRNA) based biomarker with multiple gene targets is a major challenge in the era of post genomics and the ability to apply an accurate computational method leads to the initiation of discovering novel miRNAs. In order to identify a miRNA based target interaction among the genes which are associated in the disease pathology of Psoriasis, we obtained a list of Psoriasis related genes from a database for Genome Wide Association Studies (GWAS) and then we went on to identify the network of miRNAs which are significantly related to the GWAS of Psoriasis. Further, we performed an enrichment analysis for identifying a specific miRNA on the basis of statistical tests to predict the miRNA which has the potential to become a biomarker. Finally we have identified the binding of the selected miRNA with the genes which are associated with Psoriasis. At present we have applied the above mentioned protocol for Psoriasis and in future this protocol can also be applied to other diseases. Key words: Biomarker, Pathology and Psoriasis. Psoriasis is a chronic skin disease and there is currently no permanent cure for Psoriasis. Psoriatic skin displays an inflammatory response by scaly lesions with an aberrant change in the gene expression 1 . Recent studies have revealed the fact that miRNAs play a vital role in regulating a class of post-transcriptional genes in Psoriasis. Micro RNA belongs to the family of non coding RNAs (ncRNA) which were discovered in 1993 by Victor Amoros, it consist of 19-25 nucleotides. Micro RNAs regulate the expression of about 30% of protein-coding mRNAs in humans. Initially, Lee et al. had found lin-4 as a regulator of developmental timing in Caenorhabditis elegans 2 . After several years, Reinhart et al. had discovered lethal-7 (let-7) gene in Caenorhabditis elegans 3 . Currently there are about 2500 miRNAs in the human genome. Majority of miRNA are intragenic 4 . Micro RNAs are initially transcribed as part of an RNA stem-loop that in turn forms a part of a several hundred nucleotides long precursor (pri-miRNA) 5 . Mature miRNA is a part of an RNA-induced silencing complex (RISC) which contains Dicer and many associated proteins 6 . Since miRNA is involved in the functioning of eukaryotic cells, dysregulation of miRNA been associated with disease and a miR2Disease database contain documents with known relationships between miRNA dysregulation and human disease 7 . Micro RNAs can bind to target messenger RNA (mRNA) transcripts of protein-coding genes and negatively control their translation or cause mRNA degradation and the key factor is to identify the vital target of miRNA with accuracy. A detailed review for the advances in the miRNA target identification methods are available from the resources published by Zheng et al. 8 . Several other methodologies were also proposed on the basis of