Detection of 6pLOH in an aplastic anemia patient by in phase HLA genotyping

Recent studies have reported loss of heterozygosity in the chromosome 6p arms (6pLOH) of acquired aplastic anemia (AA) patients, and in tumor cells trying to escape the autoimmune system. We thus sought to establish detection methods for LOH to investigate the mechanisms underlying AA and tumor immunity. Herein, we report our evaluation of 6pLOH in a patient with severe AA patient using super‐high resolution, single‐molecule, sequence‐based typing (SS‐SBT). The highest ratios of 6pLOH detection were observed during the patient's treatment with granulocyte colony stimulating factor (G‐CSF). This result suggested that most of the neutrophil precursor cells stimulated by G‐CSF already had LOH in the HLA lesion. The SS‐SBT method is a simple NGS method that provides complete HLA allele coverage.