Deletion of the HLA-B Gene in One of the Inherited Haplotypes in a Northern European Family

Targeted next generation sequencing-based HLA typing of a 17-year-old female transplant patient showed homozygosity for the HLA-B allele. The segregation analysis of HLA haplotypes of family members only allowed the conclusion that the B-allele was deleted in the haplotype inherited from the father and accordingly paternal grandfather, resulting in false homozygous genotyping. The subsequent whole-genome sequencing of the patient and her father confirmed an approximately 85 kb deletion at 6p21.33 from the 5' end of the HLA-B to the 3' end of the HLA-C gene extending telomeric to HLA-C.