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Thrombocytopenia-absent radius syndrome.
1Department of Clinical Genetics, Spectrum Health Hospitals, Grand Rapids, Michigan, USA. Toriello@msu.edu
Seminars in Thrombosis and Hemostasis
|November 22, 2011
Summary
Thrombocytopenia-absent radius (TAR) syndrome involves absent radii, present thumbs, and low platelets. A chromosome 1q21.1 microdeletion is common, but another genetic factor is likely involved.
Area of Science:
- Genetics
- Pediatrics
- Hematology
Background:
- Thrombocytopenia-absent radius (TAR) syndrome is a rare genetic disorder.
- It presents with bilateral radial aplasia, thumb presence, and thrombocytopenia.
- The thrombocytopenia typically resolves during childhood.
Purpose of the Study:
- To summarize the key features and current understanding of TAR syndrome.
- To highlight the genetic basis and ongoing research into its pathogenesis.
Main Methods:
- Review of existing literature on TAR syndrome.
- Analysis of genetic findings, including the 1q21.1 microdeletion.
Main Results:
- TAR syndrome is characterized by specific physical and hematological abnormalities.
- A recurrent microdeletion at chromosome 1q21.1 is identified in affected individuals.
- This microdeletion alone does not fully explain the syndrome's development.
Conclusions:
- The etiology of TAR syndrome is multifactorial, involving the 1q21.1 microdeletion and an additional genetic factor.
- Further research is needed to identify the second genetic alteration and elucidate the pathogenesis of TAR syndrome.
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