QUALITY-CONTROL OF CGH - IMPACT OF METAPHASE CHROMOSOMES AND THE DYNAMIC-RANGE OF HYBRIDIZATION

With the recent rapid expansion in the use of the comparative genomic hybridization (CGH) technique, increased attention to quality control is essential, In the present study, we show that despite optimization and standardization of metaphase preparation techniques and the commer cial availability of metaphase spreads, batch-to-batch variability of the preparations remains a significant problem. To facilitate reliable CGH analysis despite this variability, we have developed a rapid dena turation test to assess the quality of the preparations without hybrid ization and quantitative image analysis criteria for assuring the day- to-day quality of CGH experiments, including sensitivity, specificity, and dynamic range, Monitoring the dynamic range of the hybridizations was found to be particularly critical for achieving sensitive and rel iable CGH results. This reliability can be achieved, for example, by h ybridization of a green-labeled normal male DNA against red-labeled fe male DNA and monitoring of the green:red ratio of the X chromosome in relation to that of the autosomes. (C) 1997 Wiley-Liss, Inc.