Identification of two cosmids derived from within chromosomal band 3p21.1 that contain clusters of rare restriction sites and evolutionarily conserved sequences.

We have isolated large numbers of human recombinants from a cosmid library constructed from an interspecific (hamster/human) somatic cell hybrid whose only human component is an intact chromosome 3. Unique sequence probes were isolated from these recombinants and were used to localize them along the length of chromosome 3 by hybridization to a somatic cell hybrid deletion panel. We identified two cosmids, cA84 (D3S92) and cA199 (D3S93), derived from within chromosomal band 3p21.1. Both cosmids contained multiple rare restriction sites that were tightly clustered within the cosmids. We have therefore identified, in a region consistently deleted in a variety of lung cancers, two cosmids that may contain genes that are candidates for involvement in lung cancer.