ASXL

ASXL refers to a family of genes, ASXL1, ASXL2, and ASXL3, which play a role in gene regulation. These genes are involved in epigenetic processes, specifically influencing how DNA is packaged and accessed by the cell. This packaging, known as chromatin, is crucial for controlling which genes are turned on or off. The proteins produced by ASXL genes interact with other proteins that modify histones, the proteins around which DNA is wound. These modifications can lead to either a more open or more closed chromatin structure, thereby impacting gene expression.

Mutations in ASXL genes have been linked to a group of developmental disorders collectively known as ASXL-related disorders. These disorders are often characterized by intellectual disability, distinctive facial features, and overgrowth. ASXL1 mutations are most commonly associated with Bohring-Opitz syndrome and Shprintzen-Goldberg syndrome. ASXL2 mutations have also been implicated in developmental delay and skeletal abnormalities. ASXL3 mutations are known to cause Bainbridge-Ropers syndrome, a condition featuring intellectual disability, developmental delay, and a characteristic facial appearance. The precise mechanisms by which ASXL gene mutations lead to these complex phenotypes are still under investigation, but it is understood that disruptions in epigenetic regulation underlie the developmental abnormalities observed. Research continues to explore the precise functions of ASXL proteins and the downstream effects of their dysfunction.