Abstract: Objective To study RHD genotyping and RhD alloimmunization among perinatal women with RhD initial typing negative,and further accumulate relevant data for RhD-HDFN diagnosis and early intervention consensus. Methods Confirmatory test for Rh negative and RhCcEe phenotyping were performed by conventional serological methods. The screening of unexpected antibody was conducted by salt medium and antiglobulin methods. Further,specificity of antibodies and antibody titer were determined. DNA was extracted and RHD genotyping was detected by PCR-SSP and sequencing. Results Among 108 samples,6 cases were positive in RHD confirmatory test,and the most common Rh types were ccee （61 cases） and Ccee （37 cases）. According to RHD genotyping,a total of 67 cases of RHD*01N.01,23 cases of RHD*01EL.01（Asia type DEL）,10 cases of RHD*01N.03,2 cases of RHD*06.03.01,3 cases of RHD*15,1 case of RHD*05.03, 1 case of RHD*01W.33,1 case of RHD*01N.25 mutation and 1 case of new allele c.509 T>G（Genbank：MW923730）were detected. Unexpected antibodies were detected in 11 samples,including 1 case of anti-D and anti-C （RHD*01N.01）,10 cases of anti-D （8 cases of RHD*01N.01,1 case of RHD*01N.03, and 1 case of RHD*06.03.01）. None of anti-D was detected in 23 cases of Asia type DEL . Conclusion There are many variants of RHD gene,and each subtype may have different immune states of anti-D. No Asia type DEL has been found to produce anti-D,which has a low risk of anti-D alloimmunity.

Key words: RhD initial typing negative perinatal women, RhD isoimmunization, Asia type DEL