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经Ｂ９５ａ细胞系纯化分离的三株麻疹病毒Ｆｕ、ＩＭＡ、ＳＭＤ的血凝试验（ｈｅｍａｄｓｏｒｐｔｉｏｎ，ＨＡＤ）为阴性，但将它们分别感染Ｖｅｒｏ细胞并传代培养后其血凝试验由阴性转变为阳性。实验证明这种血凝表型的转变与血凝素基因Ｈ（ｈｅｍａｇｇｌｕｔｉｎｉｎ）的表达与吸附无关。以ＰＣＲ扩增血凝素基因Ｈ和融合基因Ｆ（ｆｕｓｉｏｎ），并分别进行序列分析。表明三株病毒在两种培养细胞中传代后其融合基因Ｆ的序列未发现差异。但血凝素基因Ｈ的序列却有显著的点突变并伴随血凝表型的转变。其中Ｆｕ毒株的血凝素第４８１位由Ａｓｎ（ＨＡＤ阴性）转变为Ｔｙｒ（ＨＡＤ阳性）。ＩＭＡ毒株的血凝素第１４位由Ａｓｐ（ＨＡＤ阴性）转变为Ａｓｎ（ＨＡＤ阳性），第５４６位由Ｓｅｒ（ＨＡＤ阴性）变为Ｇｌｙ（ＨＡＤ阳性）。ＳＭＤ毒株在第５４６位由Ｓｅｒ（ＨＡＤ阴性）变为Ｇｌｙ（ＨＡＤ阳性）。鉴于三株病毒血凝素基因Ｈ的点突变主要发生在３′末端，而且其中两株病毒的点突变发生在同一位点（核苷酸第１６３６位，对应的氨基酸第５４６位），５′端的点突变或是沉默突变或是与血凝性转变无关，故本文证实麻疹病毒在不同培养细胞中血凝作用的转变是血凝素基因Ｈ３′末端碱基点突变的结果?
The hemagglutination test (HAD) of the three measles viruses Fu, IMA and SMD purified by the B95a cell line was negative, but their haemagglutination test turned negative from positive to negative when they were respectively infected with Vero cells and subcultured. Experiments show that this hemagglutination phenotype changes and the hemagglutinin gene H (hemagglutinin) expression and adsorption has nothing to do. The hemagglutinin gene H and the fusion gene F (fusion) were amplified by PCR and sequenced separately. The results showed that there was no difference in the sequence of the fusion gene F after passage of the three viruses in two kinds of cultured cells. However, the sequence of the hemagglutinin gene H has a significant point mutation accompanied by a change in the phenotype of the hemagglutination. Among them, the 481 hemagglutinin of the Fu strain was changed from Asn (HAD negative) to Tyr (HAD positive). The 14th of the hemagglutinin of IMA strain was changed from Asp (HAD negative) to Asn (HAD positive), and the 546th was Ser (HAD negative) to Gly (HAD positive). The SMD strain changed from Ser (HAD negative) to Gly (HAD positive) at position 546. Since point mutations of the hemagglutinin gene H of the three viruses mainly occur at the 3 ’end, point mutations of the two viruses occur at the same site (nucleotide 1636, corresponding to amino acid 546) and 5’ Point mutations or silent mutations or has nothing to do with the change of hemagglutination, so this paper confirms the transformation of hemagglutination of measles virus in different cultured cells is the result of base point mutation of H3 ’end of hemagglutinin gene.