Marfan syndrome (MFS) is an inherited connective tissue disorder. As the spinal growth depends on delicate balance of forces, conditions that affect musculoskeletal matrix often lead to spinal deformities. A large cross-sectional study revealed a 63% prevalence of scoliosis among patients with MFS. Multi-ethnic genome-wide association studies and analyses of human genetic mutations showed that variations and mutations of G protein-coupled receptor 126 (GPR126)locus are associated with multiple skeletal defects, including shorter stature and adolescent idiopathic scoliosis. The study included 54 patients with MFS and 196 control patients. The DNA was extracted from peripheral blood using the saline expulsion method and single nucleotide polymorphism (SNP) determination was carried out using TaqMan probes. Allelic discrimination was performed by RT-qPCR. Significant differences in genotype frequencies were found for SNP rs6570507 in relation to MFS and sex (recessive model, OR 2.46, 95% CI 1.03 -5.87; P = 0.03) and rs7755109 (overdominant model, OR 0.39, 95% CI 0.16-0.91; P = 0.03). The most significant association was found in SNP rs7755109, where the frequency of genotype AG was significantly different between MFS patients with scoliosis and those without (OR 5.68, 95% CI 1.09-29.48; P=0.04). This study, for the first time, examined the genetic association of SNP GPR126 with the risk of scoliosis in patients with connective tissue diseases. The study revealed that SNP rs7755109 is associated with the presence of scoliosis in Mexican patients with MFS.