The PCR reactions were performed with 1 mL of DNA and 1 mL multiple PCR primers (the concentration was 1 mM) in a total volume of 20 mL containing 16 HotStarTaq buffer, 2.0 mM Mg 2+ , 0.3 mM dNTP, and 1 U HotStarTaq polymerase (Qiagen, Hilden, Germany). The cycling conditions for FCGR2A and FCGR3A were 95uC for 2 min, 35 cycles using 96uC for 20 s, 62uC for 2 min, and 72uC for 3 min, then 72uC for 10 min, and finally kept at 4uC. The cycling conditions for FCGR2B and FCGR3B were 95uC for 2 min, 7 cycles using 96uC for 20 s, 55uC for 2 min, and 72uC for 3 min, then 72uC for 10 min, and finally kept at 4uC. PCR products were then purified (add 1U SAP enzyme to 10 mL PCR products, incubate at 37uC for 1 hour, then, inactivate at 75uC for 15 min).