Objective To study the molecular mechanism of Bel subtype caused by mutation p.R168W of glycosyltransferase B.Methods Serological test,SSP-PCR and direct sequence the Exon6 and Exon 7 of the ABO gene.Construct a 3D molecular model and predict the structural impact of GTB protein mutations.Results A antigen or B antigen can't be detected on the surface of the propositus' RBC,and only anti-A antibodies were detected in her serum.But serological test indicated her daughter's blood type was a normal B type.SSP-PCR test indicated propositus' ABO gene type is O1 B.By gene sequencing the Exon 6 and Exon 7 of the ABO gene,a ABO Bel allel(c.502C＞T,p.R168W)was discoverd in both the propositus and her daughter.Through the propositus' daughter coexisted Bel gene with normal B gene,her blood type was a normal B type.Conclusions ABO gene c.502C＞T mutations cause Bel phenotypes in patients by reducing the stability of GTB.

【Objective】 To compare the transfusion effects of ABO homotype leukocyte depleted suspended RBC and washed RBC in patients, who present major and minor cross-match incompatibility, DAT+, IAT+ and autoantibody+ . 【Methods】 The hemoglobin and total bilirubin of patients before and after transfusion were detected, and statistical analysis was conducted by IBM SPSS Statistics 22.0 software. 【Results】 34 transfusions were performed in 17 patients with major and minor cross-match incompatibility. Both leukocyte depleted suspended RBC and washed RBC significantly increased Hb level(P<0.001)but not TBIL level(P>0.05), with similar transfusion efficacy(P>0.05). After t, Hb levels(g/L) increased by 11.35±8.07 and 13.94±9.017, and TBIL(μmol/L) decreased by 25.76±88.63 and 6.91±9.39, respectively, after the transfusion of leukocyte depleted suspended RBC and washed RBC per unit. 【Conclusion】 For blood recipients with major and minor cross-match incompatibility, both ABO homotype leukocyte depleted suspended RBC and washed RBC, given in time, were effective. However, washed RBC is secondary choice due to long preparation time and short storage time.