Incompleteness of HG002 IGH assemblies. (A) Schematic representation of the diploid IGH assembly of HG002 aligned to our custom IGH reference. Haplotype 1 (H1) and haplotype 2 (H2) correspond to the maternal and paternal chromosomes, respectively, as derived from the T2T assemblies. The top track displays the IGH gene regions, and the bottom track shows the alignment intervals of HG002 assemblies as blue boxes, with large deletions indicated by solid red lines. (B) Annotation of HG002 IGH assemblies. Empty cells indicate deletion of a gene, and the color of the cell corresponds to the matched allele sequence from the IMGT database. Sequences with no identical match are denoted as “novel.”