Interspecific hybridization between human and mouse somatic cells: Enzyme and linkage studies

Human-mouse somatic cell hybrids have been isolated and examined for enzyme and chromosome constitution. The enzymes assayed were lactate dehydrogenase (LDH), isocitrate dehydrogenase (IDH), NADP-dependent malate dehydrogenase (MDH), glucose 6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), phosphoglucomutase (PGM), and several esterases. Coexpression of mouse and human genomes and formation of heteropolymeric enzymes were observed in seven different hybrid populations for the enzymes LDH, IDH, MDH, and G6PD. Evidence predicated on the absence of chromosomal rearrangements is provided for the lack of genetic linkage in the human genome for these four enzymes, as well as for thymidine kinase.Supported in part by NIH Grants GM 09966 and 1-F1-GM-39,399 from the Institute of General Medical Sciences and by NIH Training Grant HD-32.