[Application of array-based comparative genomic hybridization in precise diagnosis of unbalanced chromosome aberration].

Objective To evaluate the method of array-based comparative genomic hybridization (array-CGH) in identifying unbalanced chromosome aberrations. Methods Four cases that could not be diagnosed by conventional cytogenetic technique were selected to undergo array-CGH analysis. DNA samples were extracted and hybridized with the Affymetrix SNP 6.0 arrays using Human Mapping SNP6.0 assay kit following the manufacturer's standard protocol. The data were analyzed by two professional software packages, GCOS and Genotyping Console. Results By using array-CGH technique, all the four cases were diagnosed precisely through identifying two duplications and two complex derivative chromosomes. Conclusion Array-CGH is an effective method for whole-genome identification of unbalanced chromosomal aberrations with high sensitivity and specificity. It has a great value to investigate the correlations between genotype and phenotype in clinical service, especially in prenatal diagnosis. Key words: array-based comparative genomic hybridization; unbalanced chromosome aberration; genotype-phenotype relationship