COL13A1 encodes collagen type XIII alpha 1 chain, a transmembrane collagen with a cytosolic domain, transmembrane region, and collagenous ectodomain 1. The gene is located on chromosome 10 and contains 42 exons spanning approximately 135 kilobases 1. Primary Function: COL13A1 mediates cell-matrix and cell-cell adhesion interactions essential for normal development 2. It may participate in muscle fiber-basement membrane linkage and endochondral bone ossification 2. At neuromuscular junctions, COL13A1 plays a role in acetylcholine receptor clustering 2. In pancreatic islet endothelial cells, COL13A1 functions as a structural gene component of the vascular microenvironment 3. Mechanism: COL13A1-expressing cancer-associated fibroblasts produce chemokines that recruit macrophages and regulatory T cells while limiting dendritic cell and T cell recruitment 4. Cancer cells produce COL13A1 to promote tumor budding and invasion through invadopodia formation 5. COL13A1 expression is downregulated by the EP2 receptor agonist omidenepag in trabecular meshwork cells, contributing to aqueous humor outflow enhancement 6. Disease Relevance: Pathogenic variants in COL13A1 cause congenital myasthenic syndrome (CMS), characterized by impaired neuromuscular signal transmission 2. COL13A1 variants associate with elevated transaminase levels and non-alcoholic fatty liver disease risk in admixed Mexican populations 7.