Using a non-radioactive PCR-SSCP technique, we identified a novel glucose-6-phosphate dehydrogenase (G6PD) mutation in a Chinese newborn with neonatal jaundice. This new variant (G6PD NanKang) causes a T to C change at nucleotide position 517, producing a Phe173Leu substitution in the human G6PD protein. Since the 517 mutation does not create or remove any known restriction site, we introduced an artificially created site by adding a primer containing a mismatched base to the PCR reaction mixture. The mismatched base accompanying the nearby 517 T-->C mutation generates an XhoI site which is suitable for distinguishing normal from mutant alleles. Using this approach, the 517 mutation can be diagnosed quickly at the DNA level.