RESUMO
Objective@#To explore the relationship between MSX1 gene detection and tooth loss in a Van der Woude syndrome (VWS) family @* Methods @# DNA was extracted from the venous blood of 2 patients with dental hy⁃podontia in the 9th family of Van der Woude syndrome (VWS) families and 62 controls with complete dentition. Primers were designed for the MSXl gene. The coding regions of exons 1 and 2 of the MSX1 gene were amplified by PCR. The purified products of exons 1 and 2 of the MSX1 gene were sequenced and analyzed by sequence alignment @*Results@#The ivs2+68 C>T polymorphism in the MSX1 gene was found in the VWS9 members with tooth loss, and the VWS pa⁃tients with IRF6 gene mutations had increased tooth loss@* Conclusion@#Congenital tooth loss in the patients with con⁃genital missing teeth in VWS family 9 may be related to the ivs2 + 68 C> T polymorphism of the MSX1 gene.