Genetic polymorphisms of collagen type I α1 chain (COL1A1) gene increase the frequency of low bone mineral density in the subgroup of children with juvenile idiopathic arthritis.

Background: Collagen type I is one of the key proteins involved in the maturation, development and mineralization of bone. Genetic polymorphisms of collagen type I alpha-1 chain (COL1A1) gene are associated with low bone mineral density and higher risk of fractures in adults and children. We hypothesize that the polymorphic alleles and genotypes of COL1A1 gene influence bone mineralization and metabolism in children with juvenile idiopathic arthritis (JIA).