Chapter 30 : Microarrays and Genome Analysis

Abstract:

This chapter deals with an activity that is an interactive computer simulation of a microarray analysis of gene expression in normal and cancer cells. Hybridization analysis allows scientists to ask questions about specific nucleic acid sequences. A microarray resembles a tiny checkerboard on a glass slide about the size of a coverslip. Microarray manufacturers will design a number of different probes to different portions of the same gene. In fluorescence in situ hybridization or Southern hybridization, the probe DNA is labeled. With microarrays, the probes sit on the gene chip and labeled sample is applied to them. When DNA samples are analyzed by microarrays, the goal is to get information about the genotype. The sample is hybridized to probes that represent many different alleles of genes, and the genotype is revealed by the hybridization patterns. Computerized scanners read the chips after hybridization and interpret the patterns of hybridization into information about specific genes or sequences. Genotyping by microarray allows an investigator to analyze which allele among many possibilities is present in an individual’s genome at many loci simultaneously. One application for which this can be very helpful is genetic mapping.