TIMP2 Polymorphisms Association With Curve Initiation and Progression of Thoracic Idiopathic Scoliosis in the Caucasian Females

Idiopathic scoliosis (IS) etiology remains unclear, but strong genetic background is suggested. Previously reported TIMP2 study indicates an association of genic rs8179090 with IS progression in a Han Chinese population. However, there has been a lack of investigation into intragenic TIMP2 polymorphisms in IS patients. We recruited 100 Caucasian females with IS and 100 controls. Patients were subdivided accordingly to: progression rate, curve severity, joint mobility, and curve pattern. Allele-specific-polymerase chain reaction based on fluorescence resonance energy transfer was applied to evaluate nine TIMP2 polymorphisms. Distribution of genotype and allele frequency in only one polymorphism (rs11658743) differed in case-control study. Four of the polymorphisms (rs2277700, rs11077401, rs2376999, and rs4789934) showed non-equal distributions either in genotype or/and allele distributions in the patients of different progression rates. The rs11077401 was related to curve severity patients distinction and the rs8179090 distinguished patients with different joint mobility level. Two polymorphisms either differed statistically in case of curve patterns subgrouping (rs8068674 and rs8179090) or showed a slight tendency toward significance in the recessive model of allele distributions (rs9916809 and rs8179090). The remaining two polymorphisms (rs2377005, rs11658743) showed no association with either clinical or radiographic IS characteristics. The influence of the G allele of the rs8179090 on the clinical course of IS has not yet been confirmed. We identified four TIMP2 polymorphisms (rs11077401, rs2376999, rs2277700, and rs4789934) that were associated with a higher risk of the progressive IS form. Further genetic association studies based on suggested clinical criteria would be necessary to validate TIMP2 polymorphisms associated with the curve progression. (c) 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2217-2225, 2019