人X染色体专性DNA片段的分离和鉴定

ISOLATION AND CHARACTERIZATION OF HUMAN X CHROMOSOME DNA SEGMENTS

Random single-copy DNA segments were isolated from Los Alamos human Xchromosome library. The library was screened three times for nonrepetitive DNAinserts by plaque in situ hybridization to total human and mouse DNA. Out of 100plaque forming units (pfu), one to two single-copy recombinants, were obtained.DNAs from clones containing single-copy inserts were labeled by nick translationand Southern hybridization to normal human, and mouse DNA, and to a panel ofcell hybrid DNAs either retaining X chromosome or not retaining X chromosome.Human single-copy DNA segments isolated were all localized on X chromosome.Three segments, namely DXFD 52, DXFD 73, DXFD 75 were mapped to X chro-mosome. These segments will be further precisely localized to regions on X chro-mosome by in situ chromosomal hybridization.