[Molecular Biological Mechanism and Transfusion Strategy of a Jk(a-b-) Family].

Objective: To investigate the molecular mechanism and explore blood transfusion strategies for a proband exhibiting the JK (a-b-) phenotype and anti-JK³ high frequency antigen antibody and her eight family members.

Methods: The Kidd blood phenotype and irregular antibodies in a family were identified by serologic tests. Exon 4-11 and intron region of SLC14A1 gene were sequenced by Sanger method.

Results: The combination of the gene JK*B (c.499A>G,c.512G>A,c.588A>G) and gene JK*B (c.342-1G>A,588A>G) in this family were considered to result in the JK (a-b-) phenotype in two members. The members carrying gene JK*A(c.130G>A,588A>G) all present serological JK^a+W. Members carrying gene JK*B (c.499A>G,c.588A>G) all present serological JK^b+W, which has not been previously reported to cause antigenic weakening. The proband with JK (a-b-) phenotype produced anti-JK³ antibodies, the hospital formulated a number of blood preparation strategies for the patient and she was discharged after recovery.

Conclusion: In this study, the molecular mechanism of JK (a-b-) in this family was identified, the transfusion strategy of rare blood group was established in our institution preliminary, and the necessity of establishing a rare blood group bank was revealed in this region. It is suggested that JK*B (c.499A>G,c.588A>G) may be a new genetic pattern leading to the weakening of Kidd antigenicity, which lays a foundation for the study of population genetics.