Investigation of a Novel LRP6 Variant Causing Autosomal-Dominant Tooth Agenesis

• Main Authors: Yan-xia Huang, Chun-yan Gao, Chun-yan Zheng, Xu Chen, You-sheng Yan, Yong-qing Sun, Xing-yue Dong, Kai Yang, Dong-liang Zhang
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2021-07-01
• Series: Frontiers in Genetics
• Subjects: tooth agenesis; LRP6 gene; whole-exome sequencing; molecular dynamics analysis; experimental study
• Online Access: https://www.frontiersin.org/articles/10.3389/fgene.2021.688241/full

BackgroundThe low-density lipoprotein receptor-related protein 6 (LRP6) gene is a recently defined gene that is associated with the autosomal-dominant inherited tooth agenesis (TA). In the present study, a family of four generations having TA was recruited and subjected to a series of clinical, genetic, in silico, and in vitro investigations.MethodsAfter routine clinical evaluation, the proband was subjected to whole-exome sequencing (WES) to detect the diagnostic variant. Next, in silico structural and molecular dynamics (MD) analysis was conducted on the identified novel missense variant for predicting its intramolecular impact. Subsequently, an in vitro study was performed to further explore the effect of this variant on protein maturation and phosphorylation.ResultsWES identified a novel variant, designated as LRP6: c.2570G > A (p.R857H), harbored by six members of the concerned family, four of whom exhibited varied TA symptoms. The in silico analysis suggested that this novel variant could probably damage the Wnt bonding function of the LRP6 protein. The experimental study demonstrated that although this novel variant did not affect the LRP6 gene transcription, it caused a impairment in the maturation and phosphorylation of LRP6 protein, suggesting the possibility of the disruption of the Wnt signaling.ConclusionThe present study expanded the mutation spectrum of human TA in the LRP6 gene. The findings of the present study are insightful and conducive to understanding the functional significance of specific LRP6 variants.