COSMID CLONES FROM MICRODISSECTED HUMAN CHROMOSOMAL REGION-15Q11-Q13

A human chromosomal region, 15q11-q13, was microdissected, its DNA was amplified with the primer-linker PCR method, and the PCR products wer e cloned into a plasmid vector to construct a microclone library. Of 1 93 microclones analyzed with Southern blot hybridization on hybrid cel l panels, 26 (13.5%) were either single-copy (unique) or low-repetitiv e fragments. By screening of a cosmid library of human genomic DNA usi ng the 26 microclones as probes, 47 positive cosmids were obtained and underwent regional mapping with chromosome fluorescence in situ hybri dization (FISH). Sixteen cosmids gave FISH signals at 15p-cen, 5 at 15 q11-q13, 6 at 15q22-q26, 3 at other chromosomes, and 17 no signal. The se 27 cosmids mapped to chromosome 15 are useful additions to the inve ntory of DNA markers of this chromosome including the much interested Prader-Willi/Angelman syndrome region.