摘要目的:报告1例类孟买血型并探讨其分子机制。方法:对1例ABO血型常规检测正反定型不相符的就诊者，采用吸收放散试验检测红细胞弱表达的ABH血型抗原，唾液酸实验检测唾液中血型物质。采用PCR产物直接测序法进行 ABO基因第6、7外显子和 FUT1和 FUT2基因序列分析。 结果:ABO血型正定型为O型，反定型为AB型，唾液中检测到有H和A、B物质，直接测序发现先证者 FUT1基因存在c.35C>T、c.328G>A、c.504delC复合杂合变异，单倍型序列分析表明先证者的 FUT1基因型为h 328A/h 35T+504delC，已上传NCBI，序列号为MW323551。 结论:本研究发现了1例由 FUT1基因复合杂合新变异c.504delC引起的类孟买表型AB mh，该变异可能影响糖基转移酶的活性，导致其酶的功能缺陷。

abstractsObjective:To explore the genetic basis for an individual with a para-Bombay phenotype.Methods:A proband with mismatched forward and reverse serotypes for the ABO blood group was identified. Weakly expressed ABH blood type antigen on the surface of red blood cells was verified by absorption and release test, and the blood group substances in saliva was detected by sialic acid test. Exons 6 and 7 of the ABO gene and exons of the FUT1 and FUT2 genes were subjected to direct sequencing. Results:The proband was found to be of O type by forward ABO serotyping and AB type by reverse ABO serotyping, though H and substance A and B were detected in her saliva. DNA sequencing revealed that she has harbored c. 35C/T, c. 328G/A, and c. 504delC compound heterozygous variants of the FUT1 gene. Haploid analysis showed that her FUT1 genotype was h328A/h35T+ 504delC, which has been uploaded to the NCBI website (No. MW323551). Conclusion:The para-Bombay phenotype of the proband may be attributed to the novel compound heterozygous variants including c. 504delC of the FUT1 gene, which may affect its function by altering the activity of FUT1 glycotransferase.