AIM: The purpose of the study was to evaluate the feasibility and reliability of comparative genomic hybridization (CGH) in the detection of genomic imbalances in Chinese malformed fetuses.
METHODS: Genomic DNA was extracted from umbilical cord blood or fresh amniotic fluid of 9 malformed fetuses and labeled with SpectrumGreen dUTP or SpectrumRed dUTP. A pair of CGH analyses in which the fluorochromes were exchanged was carried out for each sample.
RESULTS: Samples from 9 malformed fetuses were analyzed successfully by CGH. Numerical chromosome aberrations were detected in samples from cases 4, 8 and 9, and were verified by fluorochrome-exchanged CGH. Trisomy 21q was detected in case 4, del 2p24-pter and dup 12p13 was detected in case 8, and del 1p33-pter and del 22q11-12 were detected in case 9.
CONCLUSION: CGH is a reliable technique for the detection of genomic imbalances. Fluorochrome-exchanged CGH can reduce inconsistencies in the results caused by deviations in the process of DNA labeling and hybridization, and increase the accuracy and reliability in cases when conventional cytogenetic analysis is unavailable.