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Updated: Oct 13, 2025

Isolation of Epithelial Cells from Human Dental Follicle
Published on: November 5, 2021
The phenotypic characteristics of patients with athelia and tooth agenesis
Xiaoling Chen1,2, Yan Xiang1,2, Lvli Yang2,3
1Department of Endodontics I, Stomatological Hospital of Xiamen Medical College, Xiamen, China.
Background:
Although athelia, which is a congenital aplastic deformity of the nipple, is seldom reported in tooth agenesis patients, we observed athelia in 2 hypodontia patients. This study aimed to summarize the phenotypic characteristics of patients with athelia and tooth agenesis.
Methods:
A database search was conducted for publications reporting on patients with athelia and tooth agenesis, and the phenotypes of such patients were recorded. Athelia-related syndromes were identified in the Online Mendelian Inheritance in Man (OMIM) database. The common symptoms and the causative genes were documented. Potential interactions between athelia-related genes and tooth agenesis-related genes were analyzed in the Database for Annotation, Visualization, and Integrated Discovery (DAVID) Bioinformatics Resources and the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database.
Results:
We summarized the phenotypic characteristics of 8 previously reported patients. Deformities in hair, skin, and sweat glands were common in these patients. There were 23 nipple deformity-related syndromes reported. The most common symptoms included abnormalities of the head and neck, cardiovascular, genitourinary, and skeletal systems, and the skin, nails, and hair. Hypodontia was noted in association with 10 syndromes. A total of 16 genes were related to them, including TP63, KCTD1, and IKBKG. The interaction found in the study suggests that nipple deformity-related genes potentially interact with tooth agenesis-related genes.
Conclusions:
These results indicated that athelia might be related to hypodontia. Additional molecular genetics research is needed to fully elucidate the underlying relationship between athelia and tooth agenesis.
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