Naturally occurring anti-PP1PK in a Chinese individual with p phenotype: A case based on compound heterozygosity including one novel allele

Abstract

Background: The null phenotype in P1PK blood group, known as "p," is extremely rare in the whole world. Individuals of p phenotype spontaneously form anti-PP1P^K isoantibody. Here, we report a case of p phenotype with naturally occurring anti-PP1P^K isoantibodies in a Chinese individual.

Study design and methods: Serology tests, containing alloantibodies screening and identification, were conducted to demonstrate the phenotype in P1PK blood group. The genotype of A4GALT gene was identified by haplotypes separation and sequencing.

Results: The serological assay demonstrated the p phenotype of the proband, presenting with 1:64 titer of anti-PP1P^K . The sequencing data revealed a compound heterozygote consisting of A4GALT*P1.01 with c.343A>T and a novel allele based on A4GALT*01N.05 with an addition polymorphism c.100G>A. The sequence of the novel allele has been submitted to GenBank and the accession number OM912503 was assigned.

Conclusion: Our study demonstrates a case of naturally occurring anti-PP1Pk in a Chinese individual with p phenotype, which is based on compound heterozygosity including one novel allele. As the proband is a young lady, monitoring the titer of anti-PP1P^K and early initiation of medical intervention are essential after her pregnancy.

Keywords: P1PK blood group; anti-PP1PK; novel allele; p phenotype.