Abstrait

ARX gene with an impressive role in X-linked intellectual disability

Ghadami S, Eshaghkhani Y

Intellectual disability is the most common neurodevelopmental defect in the worldwide. X-linked intellectual disability (XLID) is the frequent form of intellectual disability which includes a heterogeneous group of inherited disorders emerging as various degrees of intellectual disabilities. XLID has a prevalence of 2.6 cases per 1,000 in the general population and accounts for over 10% of all cases of intellectual disability. Based on associated phenotypes, XLID is subdivided into syndromic (S-XLID) and non-syndromic (NS-XLID) forms; where two third of XLID cases are thought to be non-syndromic. Among the non-syndromic form, the aristalessrelated homeobox gene (ARX) gene is one of the ideal candidates to be evaluated in NS-XLID, since its mutations are responsible for about 9.5% of XLID cases. The ARX is located on the Xp22.13 genomic region and encodes a highly conserved protein with a considerable role in Wnt/β-catenin signaling pathway. Base on review literature, mutations in ARX gene has a particular influence on the critical processes associated with the brain development. Our results in bioinformatics study of molecular features, second and quaternary structures of ARX gene and also the phylogeny tree of ARX protein is showed that the ARX is a highly conserved protein with a substantial role in an important developmental pathway and its deficiency can cause irreversible defects, mainly in brain, that leads to the development of XLID as a common form of intellectual disability and also, the sequence alignment of this protein with other spices confirms that the functional domains of ARX protein are highly conserved, thus it has been predicted that the mutations of this gene is highly pathogenic. Alongside, we mainly focused to gather the data addressing the structural properties of ARX protein and bioinformatics assay of this protein to find the important role of ARX gene in the integrity of normal brain development.