A technique that identifies genes based on their position on the chromosome. Positional cloning is accomplished by using linkage analysis to locate a mutation relative to a known genetic marker, followed by chromosomal jumping and walking to screen for po
Identification of a gene based on its physical location in the genome. Often, an individual has a phenotype, but the gene underlying this phenotype is unknown. Using linkage mapping, the phenotype can be assigned a position in the genome. Once a phenotype has been localized, overlapping sets of clones (for example, BACs) that cover the region are identified. Genes within the region are identified and compared to DNA from individuals that display the phenotype until the underlying mutation is identified. Read more about positional cloning references: Kerem B, et al. Identification of the cystic fibrosis gene: genetic analysis. Science 1989; 8;245(4922):1073-80.