Genotyping analysis of the stable CHO transfectants expressing NA1-, NA2-, and SH-isoforms by allele-specific PCR. DNA were isolated from the transfectants and were amplified using allele-specific NA1- (lanes 2, 5, and 8), NA2-(lanes 3, 6, and 9), and SH- (lanes 4, 7, and 10) primer. PCR products were analyzed on 1.5% agarose gel using MW VI (lane 1; Boehringer Mannheim, Mannheim, Germany) as molecular weight standards.