Genomic structural variants constrain and facilitate adaptation in natural populations of Theobroma cacao, the chocolate tree.

ABSTRACT: Genomic structural variants (SVs) can play important roles in adaptation and speciation. Yet the overall fitness effects of SVs are poorly understood, partly because accurate population-level identification of SVs requires multiple high-quality genome assemblies. Here, we use 31 chromosome-scale, haplotype-resolved genome assemblies of Theobroma cacao-an outcrossing, long-lived tree species that is the source of chocolate-to investigate the fitness consequences of SVs in natural populations. Among the 31 accessions, we find over 160,000 SVs, which together cover eight times more of the genome than single-nucleotide polymorphisms and short indels (125 versus 15 Mb). Our results indicate that a vast majority of these SVs are deleterious: they segregate at low frequencies and are depleted fro

SUBMITTER: Hamala T 

PROVIDER: S-EPMC8536383 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature