Genotyping of the ABCG2 gene using Matrix-Associated Laser Desorption/Ionisation, Time-of-Flight Mass Spectrometry

Area of Science:

• Genetics
• Molecular Biology
• Immunology

Background:

• The Jr (a-) blood group phenotype is rare in Japanese donors (approx. 0.05%).
• Understanding the genetic basis of blood group phenotypes requires advanced genotyping techniques.
• High-throughput SNP genotyping is crucial for comprehensive analysis of genes like ABCG2.

Purpose of the Study:

• To assess the utility of Matrix-Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) for ABCG2 gene genotyping.
• To determine the allele frequency of the ABCG2 gene in the Japanese population.
• To investigate the molecular basis of the Jr (a-) blood group phenotype.

Main Methods:

• Collected 1004 blood samples from Japanese Jr (a-) blood donors.
• Employed High-Resolution Melting (HRM) analysis and DNA sequencing for initial SNP identification.
• Utilized MALDI-TOF MS with specifically designed primers and probes for genotyping 205 Jr (a-) samples.

Main Results:

• Identified SNPs in 1004 Jr (a-) samples; 80% were homozygous for c.376 T.
• MALDI-TOF MS successfully genotyped 205 samples with minimal calling failures (2 samples).
• Achieved a high concordance rate (99.02%) between MALDI-TOF MS genotyping and pre-genotyping results for ABCG2 alleles.

Conclusions:

• Japanese Jr (a-) donors predominantly exhibit the homozygous c.376 T genotype.
• MALDI-TOF MS is a reliable and accurate method for ABCG2 gene genotyping, showing high concordance with existing methods.
• Further SNP detection is necessary for comprehensive JR blood group genotyping.