using brdurd-sensitive restriction and uv irradiation to identify newly synthesized dna directly on southern blots , and restriction fragment length differences to discriminate alleles on active and inactive human x chromosomes , we examined the replication of hypoxanthine phosphoribosyltransferase ( hprt ) and clotting factor ix ( f9 ) loci in clonal populations of mouse-human hybrids .
C0012854
dna
C0598312
replication