The histology department at CBI offers FISH (fluorescence in situ hybridization) as an important tool in preclinical research and toxicology. FISH is a cytogenetic technique employed to detect and localize the presence or absence of specific intracellular DNA sequences onchromosomes. FISH uses fluorescent probes that bind to chromosomal locations that demonstrate a high degree of sequence complementarity. FISH is often used for finding specific features in DNA for use in tumor research, bacteriology, genetic counseling, medicine, and species identification and may be used to detect and localize specific RNA targets (mRNA, lncRNA and miRNA) in cells, circulating tumor cells, and tissue samples, there by defining spatial-temporal patterns of gene expression within cells and tissues.