Follow-up with whole-exome sequencing analysis revealed a mutation c.2032G>A (p.Gly678Arg) in the COL2A1 gene (NCBI Reference Sequence: NM_001844.4), which co-segregated with the disease phenotype in this family, manifested by severe hip dysplasia and osteoarthritis.
The literature documents numerous private mutations in COL2A1 associated with diverse clinical phenotypes including bilateral hip dysplasia and premature osteoarthritis.
Variants in the Type II collagen (COL2A1) and vitamin D receptor (VDR) genes have been associated with patients with osteoarthritis of the hip secondary to DDH, suggesting these genes could contribute to DDH.