Researchers have made significant progress in understanding the roles of alternative DNA structures, known as non-B DNA, in great apes’ genomes. By analyzing telomere-to-telomere (T2T) genome assemblies of humans and other great apes, the team predicted the locations of these structures across the genomes.
Non-B DNA can adopt different conformations from the traditional double helix and has been linked to cellular processes and genome evolution. However, its occurrence in repetitive regions made it difficult to accurately read and assemble their sequences. The new study, published in Nucleic Acids Research, reveals that non-B DNA structures are enriched in newly sequenced genomic regions and points to potential previously unknown functions.
The research team used T2T genomes to overcome previous limitations caused by highly repetitive DNA regions. They found that non-B DNA structures were similar across ape species, with the gorilla genome containing a higher percentage of repetitive DNA also having more potential non-B DNA motifs.
Non-B DNA tends to have higher mutation rates and can be unstable, leading to chromosomal rearrangements. The researchers suggest this may play an important role in genome evolution and genetic disorders. While experimentally confirmed, most non-B DNA structures require additional confirmation.
The study provides a critical first step towards understanding the roles of non-B DNA in biological function and evolution. As scientists continue to explore the functions of novel structural characteristics in the genome, researchers hope their work will serve as a springboard for further studies.
Source: https://scitechdaily.com/beyond-the-double-helix-strange-new-dna-structures-discovered-in-ape-genomes