Replicative verification of susceptibility genes previously identified from families with segregating developmental dysplasia of the hip

Background: Developmental dysplasia of the hip (DDH) is a complex hip joint deformity with effects ranging from acetabulum malformation to irreversible hip dislocation. Previous studies suggest a significant association of four variations, teneurin transmembrane protein 3 (TENM3, OMIM * 610083) (chr4:183721398), heparan sulfate proteoglycan 2 (HSPG2, OMIM * 142461) (chr1:22201470), ATPase plasma membrane Ca²⁺ transporting 4 (ATP2B4, OMIM * 108732) (chr1:203682345), and prostaglandin F receptor (PTGFR, OMIM * 600563) (chr1:79002214), with DDH susceptibility in families with segregating DDH. However, the association was not validated in sporadic cases and remains controversial. To confirm the association of the reported variations in these four genes with DDH, we conducted replicative verification in 250 sporadic samples with DDH from a Chinese Han population.

Methods: We conducted Sanger sequencing after amplifying the variation sites. The results were compared with the reference sequence from the GRCh37 assembly in UCSC ( http://genome.ucsc.edu ).

Results: Replication analysis of 250 sporadic samples by Sanger sequencing indicated that the four variations, TENM3 (OMIM * 610083, chr4:183721398), HSPG2 (OMIM * 142461, chr1:22201470), ATP2B4 (OMIM * 108732, chr1:203682345), and PTGFR (OMIM * 600563, chr1:79002214), were not associated with the susceptibility to DDH in the Chinese Han population.

Conclusions: Further studies should be performed to identify other variations of these four genes that are potentially associated with DDH by whole-exome sequencing and the results should be verified in different populations.