Synteny between glycinamide ribonucleotide synthetase and superoxide dismutase (soluble).

The auxotrophic mutant ade -C derived from Chinese hamster ovary cell CHO-K1 lacks the enzyme glycinamide ribonucleotide synthetase and requires exogenous supplement of purines for growth. Cells from this mutant were fused with normal human lymphocytes, and the resulting hybrids were isolated in purine-deficient medium. A total of 32 primary clones and 49 secondary clones were analyzed for various isozyme markers. Cytogenetic analysis with chromosome banding was also performed in some hybrid clones. The results provide evidence indicating that glycinamide ribonucleotide synthetase is syntenic with superoxide dismutase (soluble) and is located on human chromosome 21.