Chromosomal Microarray

Genetic testing methods have changed over the years. First, there was the advent of chromosome banding methods in the 1970s to 1980s. In the 1990s, there was the isolation of DNA markers from individual chromosomes that were used with fluorescence in situ hybridization (FISH) for identification of deletions too small to be detected in routine chromosome studies. Advances in genetic technology since the 1990s initially led to a collection of thousands of DNA markers from the 23 pairs of human chromosomes for development of chromosomal microarrays. This genetic tool further identified copy number variation or submicroscopic deletions or duplications. Later, the DNA markers included probes to detect single nucleotide polymorphisms (SNPs) as well as chromosome deletions and duplications. Now these high-resolution chromosome microarrays contain over ...