[Serological and Molecular Biological Analysis of Rare Cases of p-Blood Type]

To clarify the specificity of patient blood type and blood type antibody through patient blood type serological tests and molecular biology results, and to search for matching blood for patients.

Blood type serological methods were used for the identification of red blood cell ABO, RhD, and p blood type. Salt water method, microcolumn gel method and IAT method were used for irregular antibody screening and antibody specificity identification. Forward and reverse sanger sequencing was used to amplify specifically the third exon (CDS sequence) of the A4GALT gene, identify the mutation site and genotype of the gene.

The patient's serological blood type was positive for type B and D, indicating a p phenotype. At the same time, anti-Tj^a was detected in the serum, and further sequencing of the A4GALT gene exon was performed, the homozygous mutation with G>C occurred at base 559, and the genotype ISBT was named A4GALT*01N.10. Molecular biology verification confirmed it to be p blood group. Serological methods confirm that the patient's serum contains anti-Tj^a.

The joint identification of the rare blood type-p blood type by serological and molecular biological methods is of great significance for safe clinical blood transfusion.