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TBX2 gene duplication associated with complex heart defect and skeletal malformations.
Francesca Clementina Radio1, Laura Bernardini, Sara Loddo
1Casa Sollievo della Sofferenza Hospital, IRCSS, San Giovanni Rotondo and CSS-Mendel Institute, Rome, Italy.
American Journal of Medical Genetics. Part A
|July 17, 2010
Summary
A de novo duplication of the TBX2 gene was found in a patient with developmental delays and heart defects. This suggests TBX2 gene dosage imbalance may cause similar conditions in humans and animals.
Area of Science:
- Genetics
- Developmental Biology
- Cardiology
Background:
- TBX2 is a gene crucial for cardiac and limb development, as indicated by animal models.
- Gene dosage imbalances can lead to developmental abnormalities.
Observation:
- A patient presented with mild mental retardation, growth retardation, cerebellar hypoplasia, and complex congenital heart defects.
- Skeletal anomalies including distal phalangeal hypo-aplasia were also noted.
- SNP-array analysis revealed a de novo duplication of 17q23.2, encompassing the TBX2 gene.
Findings:
- The identified genetic abnormality was a duplication of the TBX2 gene.
- This duplication suggests TBX2 gene overexpression in the patient.
Implications:
- The findings suggest that TBX2 gene overexpression, due to duplication, may cause congenital heart malformations and mild digital anomalies in humans.
- This highlights parallel consequences of TBX2 gene dosage imbalances in both animal models and human patients.
- Further research into TBX2 gene dosage effects is warranted for understanding developmental disorders.
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