The pathogenesis of ulnar polydactyly in humans
M M Al-Qattan1, M I Al-Motairi
1Department of Surgery, King Saud University, Riyadh, Saudi Arabia.
The Journal of Hand Surgery, European Volume
|February 26, 2013
Summary
Ulnar polydactyly pathogenesis is unclear. Genetic defects disrupt Gli3 protein balance, favoring the repressor form (Gli3-R), suggesting a unified cause for this congenital limb difference.
Area of Science:
- Developmental biology
- Human genetics
- Congenital disorders
Background:
- Ulnar polydactyly is a congenital limb malformation with unknown pathogenesis.
- Numerous genetic syndromes are associated with ulnar polydactyly.
Purpose of the Study:
- To propose a unified hypothesis for the pathogenesis of ulnar polydactyly.
- To investigate the role of Gli3 protein forms in ulnar polydactyly.
Main Methods:
- Analysis of genetic defects in syndromes associated with ulnar polydactyly.
- Evaluation of the balance between active (Gli3-A) and repressor (Gli3-R) forms of the Gli3 protein.
Main Results:
- Observed that genetic defects in associated syndromes disturb the Gli3 protein balance.
- Identified a relative increase in the Gli3-R protein form in affected individuals.
Conclusions:
- Hypothesize that a relative predominance of Gli3-R is the unified pathogenesis of ulnar polydactyly.
- This imbalance in Gli3 protein forms offers a novel explanation for ulnar polydactyly.
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