TDO综合征是罕见的外胚层发育不全的DLX3单基因突变导致的常染色体显性遗传病。头发、牙齿和骨发育异常是其临床表征。目前，DLX3突变导致TDO的分子机制仍不清晰。本课题组发现新的DLX3（Q178R）突变，并初步证明该突变可以影响成骨分化和功能，还能影响骨髓间质干细胞的衰老进程。首次提出“DLX3通过调控衰老进程来影响骨、毛发及牙齿发育的科学假设”。拟通过培养TDO病人和正常人的骨髓间充质干细胞，用高通量测序技术在甲基化、LncRNA和转录组水平，对DLX3调控基因进行筛选；用病毒介导的DLX3野生型和突变型基因，敲低DLX3表达的shRNA，验证差异明显的候选分子，探寻并验证调控机制；建立野生型和突变型DLX3转基因鼠模型，在体内验证并阐明DLX3在发育过程中的作用，利用CRISPR-Cas9系统精确纠正突变DLX3基因，尝试纠正小鼠疾病性状表现，为单基因遗传病的治疗提供理论基础。

Mutation of the distal-less gene (DLX3) is closely associated with Tricho-Dento-Osseous syndrome (TDO), which is an inherited autosomal dominant disorder and mainly characterized by kinky hair, dentin hypoplasia, and increased thickness and density of cranial bones. So far, although DLX3 is proved to be essential for the development of hair, teeth and cranial bones, yet the underlying mechanism how DLX3 mutation leads to TDO syndrome remains largely unknown. Our study group identifies a novel DLX3 mutation (c.533A>G, Q178R) in the world, and has demonstrated that this mutation not only can influence the osteogenic potential of bone marrow mesenchymal stem cells (BMSCs), but also alters the senescence process. We, for the first time, propose the hypothesis that DLX3 can affect the hair, teeth and bone development though regulating aging process. We plan to cultivate the BMSCs from TDO patients and normal healthy donors and take these as the experimental materials to screen the genes regulated by DLX3 on the level of DNA methylation, Lnc RNA and transcriptome through high-throughput technology. To explore the regulation mechanism of DLX3 in hair, teeth and bone formation and development, we will construct and yield the lentivirus-carrying wild type DLX3, mutant DLX3 and shDLX3, respectively, then use then to validate and evaluate the differential gene candidates found in the high—throughput data. Next, we will establish wild type DLX3 and mutant DLX3 transgenic mice to create TDO mice model, and then to confirm the mechanism in vivo through tissue section and immunostaining technology. Finally, to try to treat the pathologic features of TDO syndrome, we will design a CRISPR-Cas9 system to correct the mutation site of DLX3 in the transgenic mice. If we achieve the favorable results, they will provide us a solid theory and practice foundation to try to treat TDO syndrome as well as other genetic diseases.