ABSTRACT
<p><b>OBJECTIVE</b>To verify the DNA sequence of a sample serologically identified as CisAB.</p><p><b>METHODS</b>Forward and reverse group methods were used to determine the blood serological type of that the sample, and PCR-sequence specific primer (PCR-SSP) method was used for genotyping the sample.</p><p><b>RESULTS</b>Serologically, the forward group test showed that the sample was AB, while the reverse group test showed that the sample had the anti-B and anti-H + + +. The auto antibodies were negative. PCR-SSP assay showed the sample was CisAB01. ABO genetic locus sequencing showed c.261delG in exon 6, c.297 was homozygous AA. Mutations c.467C to T and c.803G to C were found in exon 7. A novel heterozygous mutation, c.724G to T, was detected.</p><p><b>CONCLUSION</b>The serological phenotype of the specimen was CisAB. The genotype was ABO *CisAB01 and ABO *O01. A novel mutation c.724G to T in exon 7 was identified (GenBank accession no. JF304777).</p>