Objective: To study genetic characteristics of an individual with para-Bombay phenotype and her family members.
Methods: ABO and H antigens were detected with routine serological techniques.The entire coding region of FUT1 gene was amplified by polymerase chain reaction (PCR). PCR products was purified with enzymes digestion and directly sequenced.
Results: The RBCs of the proband did not agglutinate with H antibody. The proband therefore has a para-Bombay phenotype (Bmh). Direct sequencing indicated the FUT1 sequence of the proband contained a homozygous 547-552 del AG and heterozygous 814A>G mutation, which gave rise to two haplotypes of 547-552delAG, 547-552delAG and 814A>G. The ABO blood type of the proband' s mother and sisters were all B.Sequencing of the FUT1 gene has found heterozygous 547-552 del AG, 814A>G mutations in the mother and elder sister, and heterozygous 547-552 del AG mutation in her younger sister. The FUT1 547-552 del AG and 814 A>G mutations of the proband were inherited from her mother.
Conclusion: A complex mutation of the FUT1 gene consisting of 547-55 del AG and 814 A>G has been identified in an individual with para-Bombay phenotype.