6. Evaluation of ARRAY CGH and karyotyping in detecting unbalanced structural chromosome abnormalities
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Abstract
Unbalanced structural chromosome abnormalities are causes of birth defects that cannot be explained by aneuploidy alone. These abnormalities can be detected by karyotyping or array CGH. The study aims to describe unbalanced structural chromosome abnormalities (≥ 5Mb) of the fetuses and to evaluate the value of karyotyping and array CGH techniques in detecting unbalanced abnormalities. The results of the study on 912 pregnant women who were indicated for amniocentesis showed that unbalanced structural abnormalities were found in 3.5% of all cases with amniocentesis and 18.2% of all chromosomal abnormalities. Among unbalanced structural chromosome abnormalities, 31.3% were unbalanced translocations/inversions/insertions; 28.1% were deletion/duplication syndromes and 40.6% were other abnormalities. The study results provide evidence that array CGH is more valuable than karyotyping with higher detection rate, early and accurately diagnose the location and size of abnormalities.
Article Details
Keywords
Deletion, duplication, structural chromosome, array CGH
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