Year: 2026
Type: article
Abstract: In contrast to the extensively studied translocation of large sections of DNA between chromosomes, this paper investigates the translocation of individual genes onto different chromosomes during metazoan evolution. We begin by extending the analysis of deeply conserved synteny of metazoan chromosomes reported by Simakov et al. (2022) to a set of 46 invertebrate species that have annotated chromosome-level genome assemblies, and in each species we map the extant chromosome(s) that represent the proposed 29 ancestral chromosomes. Then, for more than 6,000 gene families, we extract orthologs across the 46 species and we interrogate the patterns of chromosomes on which those orthologs reside, to determine a consensus ancestral chromosome for each gene family. A substantial proportion of families exhibit outliers, where the gene for a given species resides on an "unexpected" chromosome, and we search for and locate ancestral gene translocation events that can explain batches of unexpected chromosomes across multiple species within a clade. We compare our orthology inference under three conditions: unconstrained; constrained to expected chromosomes; and conditional, where there is a preference for expected chromosomes. For the conditional case, we identify 4,740 ancestral translocations plus 7,164 subsequent translocations (a total of 11,904 gene translocations) within the 6,495 gene families represented across our selection of 46 species from 32 clades. Correlating translocation numbers with branch length in the time tree indicates a very low translocation rate, below 1% of gene families per 100 million years (My) in our selected taxa.
Source: Genome Biology and Evolution
DOI: 10.1093/gbe/evag251
Institutions: Australian National University, Dartmouth College
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,850
OpenAlex ID: W7221158531