Objective To investigate the relationship between P-gp gene mutation and multi-drug resistance of breast cancer. Methods From March 2004 to April 2006, 52 cases of breast cancer samples were detected to sensitivity of 4 kinds of chemotherapeutic drugs by MTT. Among the most common mutation of PCR amplified P-gp genes, analysis of single strand conformation polymorphism was done in 250 base. And its nucleotied sequence and wild type P-gp were compared. Results In the 52 cases of breast cancer tissues,4kind o...