X‐Linked Intellectual Disability Genetics

Abstract

Abstract Intellectual disability (ID) is a common disability affecting 2–3% of the general population. X‐linked intellectual disability (XLID) disorders, caused by the defects of genes on the X chromosome, affect 1.7 of 1000 males. Patients with XLID require long‐term family involvement, medical care and social services with enormous attendant burden and cost. XLID is a medically important and biologically significant group of disorders for which the prospects for further progress on the understanding of their molecular basis have improved with advances in technological approaches. As such, worldwide efforts over the past 25 years have identified 124 XLID genes involved in 124 XLID syndromes and 53 nonsyndromal XLID conditions. About 70% these genes fall into three categories of biological process or function: structural molecule, catalytic activity or transcription regulatory activity. In‐depth analysis of the genes will assist with understanding not only XLID but also cognitive function and brain function in general. Key Concepts XLID conditions can be partitioned into two broad categories: syndromal and nonsyndromal Molecular analysis allows for splitting XLID conditions thought to be similar Molecular analysis allows for determining distinct XLID entities are allelic XLID proteins fall into 3–4 major categories of function Better understanding of XLID gene function may lead to treatment therapies