Detection of C1236T, G2677T/A, and C3435T polymorphism of MDR1 by amplification refractory mutation system PCR

C1236T, G2677T/A, and C3435T polymorphism of the multidrug resistance (MDR1) gene have substantial impact on expression or activity of P-glycoprotein (P-gp). We developed new methods based on amplification refractory mutation system (ARMS) to detect these polymorphisms. Tetra-primers amplification in a single tube was established to detect C1236T and C3435T polymorphism. For G2677T/A polymorphism, a two-step allele-specific amplification method was used. MDR1 genotypes of 177 Chinese subjects were determined by the methods we established. The methods we established were verified with gene sequencing. Gene frequencies of 1236C and 1236T were 37.8 and 62.2%, respectively; gene frequencies of 2677G, 2677T and 2677A were 44.1, 38.4 and 17.5%, respectively; the gene frequencies of 3435C and 3435T were 65.0 and 35.0%, respectively. The results were similar with other studies on Oriental subjects. The methods we established are simple, accurate, and economical, and can provide reliable approaches for determining MDR1 polymorphism.