Figure 2.
Panel A: A schematic representation of the HLA gene region on the short arm of chromosome 6. The diagram includes genes such as HLA-A, HLA-B, TNF, HLA-DRB1, and HLA-DPB1. The lower right panel shows the maternal haplotype carrying the extended AH8.1 haplotype with characteristic linkage disequilibrium. Panel B: A table and pedigree chart for Family 1, showing two affected individuals carrying the high-risk DQ2.5/2.5 genotype. The table includes HLA alleles such as A, C, B, DRB1, DQA1, DQB1, DPA1, and DPB1 with their respective genotypes. Panel C: A table and pedigree chart for Family 2, in which the index case carries DQ2.5 in trans due to the DQ2.2/7.5 combination. The table includes similar HLA alleles and genotypes as in Panel B. Panel D: A table and pedigree chart for Family 3, showing a child with abnormal DGP antibodies but without a DQ risk haplotype. The table includes similar HLA alleles and genotypes as in Panels B and C.
HLA genes and familial segregation of HLA alleles in three families. (A) Schematic representation of the HLA gene region on the short arm of chromosome 6. The lower right panel shows the maternal haplotype carrying the extended AH8.1 haplotype with characteristic linkage disequilibrium. (B) Family 1, showing two affected individuals carrying the high-risk DQ2.5/2.5 genotype. (C) Family 2, in which the index case carries DQ2.5 in trans due to the DQ2.2/7.5 combination. (D) Family 3, showing a child with abnormal DGP antibodies but without a DQ risk haplotype. Arrows indicate the index cases. DGP, deamidated gliadin.