Contribution of Iran in Elucidating the Genetic Causes of Autosomal Recessive Intellectual Disability.

Many genes with different inheritance modes contribute to the pathogenicity of intellectual disability (ID) making it the most known genetically heterogeneous disorder. Advanced next-generation sequencing (NGS) technologies have helped researchers identify genes underlying ID at an exponential pace. As a consanguineous country, Iran is a hotspot for discovering novel autosomal recessive intellectual disability (ARID) genes. Here, we aimed to review and compare reported ARID gene discovery both in Iran and globally, and pinpoint the research areas that need to be developed in future. We studied published articles and reviews on all known ID genes. In parallel, the gene-discovery research carried out on the Iranian population were also reviewed to determine the contribution of Iran to identifying novel ID genes. Also we tried to find supporting evidence on the causative role of novel genes identified in Iran including confirmatory functional studies and existence of more affected families. We also briefly reviewed the current therapeutic approaches under development for a subset of eligible ID cases. In total, 8% of all ID and 11.5% of all ARID genes described so far have been identified via studies on Iranian population. Functional studies have been performed on 29% of the genes identified in Iran. More than one affected family has been reported for many of these genes, supporting their causative role in ID pathogenesis. Despite the notable contribution of Iran in gene-discovery research, further functional studies on the identified genes are required.

SOX1 is correlated to stemness state regulator SALL4 through progression and invasiveness of esophageal squamous cell carcinoma.

SOX1, as a tumor suppressor, play anti-tumorigenecity role in different cells and its expression is inhibited in a variety of cancers. The aim of this study was to evaluate SOX1 expression and its correlation with cancer stem cell (CSC) markers in ESCC. Using real time PCR, the relative comparative expression of SOX1 in 40 ESCC samples was assessed compared to related margin normal tissues, and its correlation with CSC markers including SALL4, SOX2, and MEIS1 was analyzed statistically. The results revealed significant under-expression of SOX1 in ESCC in significant correlation with different indices of poor prognosis including depth of tumor invasion (P=0.02), Stage of tumor cell progression (P=0.05), and number of involved lymph node metastasis (P=0.05). Furthermore, the under-expression of SOX1 was associated significantly with SALL4 overexpression. This study was the first to evaluate SOX1 underexpression and its association with poor prognosis in ESCC. Since correlation of SOX1 and SALL4 was detected in advanced stages of ESCC progression, as well as high invasive and aggressive tumor tissues, it may be extrapolated that SOX1 expression may have critical role in inhibition of ESCC invasiveness and aggressiveness especially in advanced stages of the disease.