cosmids. from our chromosome- 19 library, that span a specific region of the 

 chromosome. As soon as we have processed about 8000 cosmids from chromosome 19 

 and have initiated the process of contig closure, we will begin to construct cosmid 

 contigs from another human chromosome, probably chromosome 3. The physical 

 mapping effort on this chromosome will be done in collaboration with several other 

 research groups. As the physical maps near completion, we will develop and exploit 

 new sequencing methods to study the molecular architecture of the chromosome and 

 new screening methods that will rapidly evaluate somatic variation and induced genetic 

 change in human populations. 



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