ISOLATION OF CHROMOSOME-SPECIFIC GENES BY RECIPROCAL PROBING OF ARRAYED CDNA AND COSMID LIBRARIES

We have identified and mapped 61 novel and previously described chromo some 17 and X genes, using a human placental cDNA library, These genes were isolated using a gene identification and mapping strategy based on reciprocal probing of arrayed chromosome specific cosmid and cDNA l ibraries, This strategy scans gridded cosmids for nuclear genes and is olates the expressed sequence by a cosmid to cDNA filter hybridization , Inherent to this approach is the advantage of identifying the corres ponding genomic cosmid clone of a particular cDNA, The genomic and cDN A reagents can be used for fluorescence in situ hybridization (FISH) a nd polymerase chain reaction (FOR) based mapping to resolve map positi ons of cDNAs belonging to gene families and those associated with mult iple chromosomes, The downstream utility of reagents generated by the reciprocal probing methods is demonstrated in our studies.