Preparation of Parental Genes

The preparation of parent genes by PCR is effective when it is difficult to excise... 

SP2 region and CH, giving rise to a recombinant Igh locus having the VH and D segments of the a haplotype and the CH genes of the b parent (Brodeur and Ri-blet, in preparation). Therefore, the Igh haplotype of C.B/R5, VHa-Da-/-CHa (where 7 indicates the cross-over), provides direct evidence for the general organization of the mouse Igh locus. 

More sensitive methods subsequently indicated the presence of a small proportion of molecules bearing markers encoded by genes on the two homologous parental chromosomes. The proportion of such molecules in doubly heterozygous rabbits was determined by Landucci-Tosi and Tosi, who utilized insolubilized antiallotype sera and I-labeled IgG preparations to quantitate allotypic specificities on individual molecules of IgG (95). They found that in a rabbit of genotype 1.4% of... 

GIueuronida.se was pro )ared from hybrid cells that were products of tissue culture C( ll lines derived from C3H (heat sensitive) and Swiss (heat stable I) mice. The deiiaturation kinetics of hybrid /3- lucuronidase were similar to a mixture of enzymes prepared from the parental cell lines or to -glucuronidase prepared from the livers of animals heteroz3 gous for this gene (Ganshow, 1906). 

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