10.22376/ijpbs.2019.10.1.p1-12 Volume 4 Issue 4 2013 (October - December) Rett syndrome (RTT) is a childhood neurodevelopmental disorder and one of the most common causes of mental retardation that primarily affects girls. Hence, there is a constant need to discover new and efficient treatment against the disease by seeking to uncover various novel alternate signaling mechanisms that can lead to Rett syndrome and its associated complications. In this present work, we used Rett syndrome microarray data to identify the significant genes by gene expression data analysis and also constructed the protein-protein interaction (PPI) networks of genes/proteins involved in the pathophysiology of RTT. We identified three high score sub lessThan b greaterThan - lessThan /b greaterThan networks from the large PPI networks and these three sub-networks have scale lessThan b greaterThan - lessThan /b greaterThan freeness topology. The functional enrichment analysis for all the genes of these three sub lessThan b greaterThan - lessThan /b greaterThan networks; we found genes from the third sub lessThan b greaterThan - lessThan /b greaterThan network have biological processes such as lessThan i greaterThan neurological disorders lessThan /i greaterThan and lessThan i greaterThan nervous system development and function lessThan /i greaterThan related to RTT. An experimental research on this sub- network and their associated genes and pathways may further provide suitable drug target identification and better understanding of the pathophysiology of RTT. SARAVANAKUMAR SELVARAJ AND JEYAKUMAR NATARAJAN Rett syndrome; Microarray data; Protein interaction networks. 845-860