The peripheral antibody repertoire is shaped by inherited genetic variation and selection during B cell development. However, how the repertoire changes across developmental stages—and the relative im...

The most dynamic and repetitive regions of great ape genomes have traditionally been excluded from comparative studies1–3. Consequently, our understanding of the evolution of our species is incomplete. Here we present haplotype-resolved reference genomes and comparative analyses of six ape species: chimpanzee, bonobo, gorilla, Bornean orangutan, Sumatran orangutan and siamang. We achieve chromosome-level contiguity with substantial sequence accuracy (<1 error in 2.7 megabases) and completely sequence 215 gapless chromosomes telomere-to-telomere. We resolve challenging regions, such as the major histocompatibility complex and immunoglobulin loci, to provide in-depth evolutionary insights. Comparative analyses enabled investigations of the evolution and diversity of regions previously uncharacterized or incompletely studied without bias from mapping to the human reference genome. Such regions include newly minted gene families in lineage-specific segmental duplications, centromeric DNA, acrocentric chromosomes and subterminal heterochromatin. This resource serves as a comprehensive baseline for future evolutionary studies of humans and our closest living ape relatives. Complete sequences of chromosomes telomere-to-telomere from chimpanzee, bonobo, gorilla, Bornean orangutan, Sumatran orangutan and siamang provide a comprehensive and valuable resource for future evolutionary comparisons.