The role of melatonin receptor genes and estrogen receptor genes in the pathogenesis of adolescent idiopathic scoliosis: A systematic review

Abstract

Objective: Adolescent idiopathic scoliosis (AIS) is the most common spinal deformity affecting healthy children. Genetic factors are thought to play a role in the etiology of this condition, along with other factors. The occurrence of the condition in twins, its early onset, and its familial predilection all support the possibility of an underlying genetic cause. This article aims to review the published studies that looked at the association of estrogen and melatonin receptor (ESR and MTNR) genes with the pathogenesis of AIS, to serve as a guide for future work and opportunities in this field. Methods: The following databases were searched: Cochrane, PubMed, Medline, Ovid, ProQuest, and ScienceDirect using relative keywords. The analysis included 14 studies. Results: Of 312 identified studies, only 14 studies (nine for ESR gene and five for MTNR gene) met our inclusion criteria. Only one study found an association between AIS susceptibility and xbal polymorphism on ESR1 gene. MTNR genes were found to be associated with AIS occurrence in large populations or when synergizing with other gene single-nucleotide polymorphisms. MTNR gene studies showed no relation with curve severity, and none of them considered curve progression, whereas five ESR gene studies considered curve progression and severity. Due to the different gene loci examined in various studies, pooled analysis of the results was not possible. Conclusion: We reviewed the genetic association of ESR and MTNR genes. Several studies found supporting evidence for both genes and their association with AIS, despite conflicting results. Further studies on different genes and different ethnic backgrounds are needed.