IBD Mapping

Identity-by-descent (IBD) mapping is a genetic mapping technique that identifies disease loci in consanguineous families or isolated populations by detecting homozygous chromosomal segments shared among affected individuals. Developed by Lander and Botstein in 1987, this method exploits the fact that rare disease alleles in related individuals must lie within shared ancestral DNA blocks. By mapping regions where affected individuals are homozygous at multiple markers, researchers can localize disease genes to narrowly defined genomic intervals without prior knowledge of the disease mechanism.