Related Experiment Video
Updated: Aug 23, 2025
07:44
Preparation of 3D Decellularized Matrices from Fetal Mouse Skeletal Muscle for Cell Culture
Published on: March 3, 2023
1.4K
Phenotypic variability in LAMA3-associated amelogenesis imperfecta
Shih-Kai Wang1,2, Hong Zhang3, Yin-Lin Wang1,2
1Department of Dentistry, National Taiwan University School of Dentistry, Taipei City, Taiwan.
Oral Diseases
|November 3, 2022
Summary
Genetic mutations in LAMA3 cause inherited enamel malformations, known as amelogenesis imperfecta (AI). This study identified novel LAMA3 mutations linked to generalized enamel defects, highlighting laminin-332
Area of Science:
- Genetics
- Biochemistry
- Dentistry
Background:
- Amelogenesis imperfecta (AI) encompasses inherited enamel malformations.
- LAMA3 encodes laminin alpha-3, a key basement membrane protein (laminin-332).
- Previous studies linked heterozygous LAMA3 mutations to localized enamel defects.
Purpose of the Study:
- To define clinical phenotypes of AI in four kindreds.
- To identify the genetic basis of AI in these families.
- To investigate the role of LAMA3 in enamel formation.
Main Methods:
- Whole-exome sequencing to identify genetic variants.
- Micro-computed tomography (μCT) to analyze enamel structure.
- Clinical phenotyping of affected individuals.
Main Results:
- Identified four novel disease-causing LAMA3 mutations.
- Observed generalized thin enamel with pits, grooves, hypoplastic bands, and hypomineralization.
- Found compound heterozygous MMP20 mutations in one patient, suggesting synergistic effects.
- LAMA3 isoforms α3A and α3B are crucial for enamel formation.
Conclusions:
- Heterozygous LAMA3 mutations cause generalized enamel defects (AI1A) with variable expressivity.
- Laminin-332 is essential for both enamel apposition and maturation.
- Genetic analysis provides insights into AI etiology and pathogenesis.
Related Concept Videos
01:33Pleiotropy
40.8K
Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...
40.8K
00:55Laminins are the Adhesive Proteins of Basal Lamina
2.2K
Laminins are heterotrimeric proteins with high molecular mass found in the extracellular matrix. Each laminin molecule is composed of three chains, viz. alpha, beta, and gamma, coded by five, four, and three paralogous genes, respectively. Laminins are categories based on the compositions of the three chains.
In humans, the five forms of alpha chains are LAMA 1, LAMA 2, LAMA 3, LAMA 4, and LAMA 5. The four forms of beta chains are LAMB 1, LAMB 2, LAMB 3, and LAMB 4. The three forms of gamma...
In humans, the five forms of alpha chains are LAMA 1, LAMA 2, LAMA 3, LAMA 4, and LAMA 5. The four forms of beta chains are LAMB 1, LAMB 2, LAMB 3, and LAMB 4. The three forms of gamma...
2.2K