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Interstitial deletion of 6q without phenotypic effect
Kerstin Hansson1, Karoly Szuhai, Jeroen Knijnenburg
1Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands. K.B.M.Hansson@LUMC.nl
American Journal of Medical Genetics. Part A
|May 17, 2007
Summary
A rare euchromatic deletion on chromosome 6 was identified in a woman with recurrent abortions. This deletion, del(6)(q22.31q23.1), had no apparent phenotypic consequences, highlighting the complexity of genetic factors in reproductive health.
Area of Science:
- Human Genetics
- Reproductive Biology
- Cytogenetics
Background:
- Cytogenetically detectable euchromatic deletions are infrequently observed without associated phenotypic abnormalities.
- Recurrent abortions can be linked to various genetic factors, including chromosomal abnormalities.
Purpose of the Study:
- To investigate the genetic basis of recurrent abortions in a 34-year-old woman.
- To characterize a cytogenetically detectable euchromatic deletion identified through karyotyping.
Main Methods:
- Conventional chromosome analysis using GTG-banding.
- High-resolution array comparative genomic hybridization (array-CGH) to precisely determine deletion size.
- Clinical examination to assess for phenotypic abnormalities.
Main Results:
- An interstitial deletion on the long arm of chromosome 6, specifically del(6)(q22.31q23.1), was identified.
- Array-CGH estimated the deletion size to be between 9.9 and 11.6 Mb.
- The patient exhibited normal intelligence and no significant dysmorphic features, apart from a common bicuspid aortic valve.
Conclusions:
- This case presents a rare instance of a cytogenetically detectable euchromatic deletion on chromosome 6 without significant phenotypic consequences.
- The identified deletion, del(6)(q22.31q23.1), may be associated with recurrent abortions, underscoring the need for comprehensive genetic evaluation in such cases.
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