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Updated: Oct 29, 2026

In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila
Published on: August 20, 2019
A missense variant in LAMB3 underlies variable expressivity in familial tooth agenesis and microdontia
B Niccolini1, C Modafferi1, G Lauretti1
1UOC Genetica Medica, Fondazione Policlinico Universitario "A. Gemelli" IRCCS, Rome, Italy.
Background:
Tooth agenesis is a frequent developmental anomaly with both syndromic and non-syndromic presentation. The LAMB3 gene, typically associated to junctional epidermolysis bullosa, has additionally been implicated in isolated dental phenotypes.
Methods:
We report a three-generation family with non-syndromic tooth anomalies, including oligodontia, microdontia, and delayed eruption. Clinical-exome sequencing was performed on the proband and their parents (trio). Variants were filtered based on frequency, inheritance, and predicted impact. Segregation was confirmed by Sanger sequencing.
Conclusion:
This report highlights the role of heterozygous LAMB3 c.547C>T variant in non-syndromic tooth anomalies and expands its phenotypic spectrum. LAMB3 should be considered in the genetic evaluation of isolated tooth agenesis, particularly in families with intrafamilial variability.
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