Construction and Use of YAC Contigs in Disease Regions

The identification of genes by positional cloning has revolutionized the molecular analysis of disease. Disease-causing genes can now be isolated with no knowledge of the biological function of the molecule involved, relying only on genetic inheritance or chromosomal perturbation as keys to isolating the gene. The key step in the positional cloning of a disease-causing gene is the conversion of the mapping information into physically cloned DNA. Advances in genomic technology, particularly in the construction, use, and accessibility of large-insert libraries, have greatly facilitated this process.