COL9A3 encodes the α3 chain of type IX collagen, a structural component of hyaline cartilage and the vitreous of the eye that contributes to extracellular matrix organization and tensile strength 1. This collagen is integrated into the interior structure of intervertebral discs 2. COL9A3 mutations cause autosomal recessive Stickler syndrome, a connective tissue disorder characterized by sensorineural hearing loss, high myopia, vitreoretinal degeneration, and skeletal abnormalities including early-onset arthropathy and spondyloepiphyseal dysplasia 341. Both homozygous and compound heterozygous pathogenic variants have been identified 1. Retinal detachment occurs in approximately 18% of cases with type IX collagen variants 1. COL9A3 mutations also contribute to pseudoachondroplasia severity; notably, combined COMP and Col9A3 mutations were found in 61% of pseudoachondroplasia cases, with some Col9A3 variants producing particularly severe phenotypes 5. Regarding intervertebral disc degeneration, meta-analyses found that the COL9A3 Trp3 polymorphism (rs61734651) alone was not significantly associated with disease risk 26. However, gene-environment interaction studies demonstrated that the Trp3 allele acts synergistically with persistent obesity to increase disc degeneration risk, with 45-71% of degeneration cases attributable to this interaction 7. COL9A3 mutations have also been implicated in skeletal dysplasias presenting with short stature 8.