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Yin, T.-T.

Publications and source records attributed to Yin, T.-T..

3 recordsLinked to original sources

Rapid evolution of fine-scale recombination during domestication

Recombination serves as a pivotal force propelling the evolution of genomic diversity in sexually reproducing organisms. Despite its fundamental role, the evolutionary dynamics of recombination rates and their implications for genome evolution remain largely elusive. The domestication of animals, which is characterized by dynamic selection pressures, offers a unique lens to explore this issue. Here, we constructed a fine-scale recombination map leveraging whole-genome data from domestic chickens, encompassing both contemporary commercial breeds and the wild progenitor, the Red Junglefowl (RJF). Our analysis revealed the rapid evolution of the recombination landscape within and across chicken populations, with significant variation in recombination coldspots and hotspots, particularly in commercial breeds. The occurrence of coldspots and the disappearance of hotspots are closely associated with selective sweeps.Contrary to prevailing observations in most species, we observed a weakly negative correlation between recombination rates and the frequency of introgressed ancestry from other RJF subspecies. Our findings provide valuable insights into the intricate interplay of evolutionary forces shaping the evolution of recombination.

evolutionary biology↗

Genomic analysis of dingoes identifies genomic regions under reversible selection during domestication and feralization

Dingoes (Canis dingo) are wild canids living in Australia. They have lived isolated from both the wild and the domestic ancestor and are a unique model for studying feralization, the process in which a domestic species escapes human control, adapts to the wild, and diverges from the domestic ancestor into a genetically distinct population. Here, we sequenced the genomes of 10 dingoes and 2 New Guinea Singing Dogs, to study the origins and feralization process of the dingo. Phylogenetic and demographic analyses show that dingoes originate from domestic dogs in southern East Asia, which migrated via Island Southeast Asia to reach Australia 4300-5000 years ago, and subsequently diverged into a genetically distinct population. Selection analysis identified 99 positively selected genes enriched in starch and fat metabolism pathways, indicating a diet change during feralization of dingoes. Interestingly, we found that 14 genes have shifted allele frequencies compared to dogs but not compared to wolves. This suggests that the selection affecting these genes during domestication of the wolf was reversed in the feralization process. One of these genes, ARHGEF7, may promote the formation of neural spine and synapses in hippocampal neurons. Functional assays showed that an A to G mutation in ARHGEF7, located in a transcription factor-binding site, decreases the endogenous expression. This suggests that ARHGEF7 may have been under selection for behavioral adaptations related to the transitions in environment both from wild to domestic and from domestic back to wild. Our results indicate that adaptation to domestication and feralization primarily affected different genomic regions, but that some genes, related to neurodevelopment, metabolism and reproduction, may have been reversibly affected in the two processes.

genomics↗

Canine transmissible venereal tumor genome reveals ancient introgression from coyotes to arctic sled dogs

Dear Editor,\n\nAncient genome-sequencing studies have extensively refined our understanding of the genetic histories and adaptive evolution of humans1, as well as the domestic process of livestock and crops2. Recent studies about ancient and modern canids all indicate that canids have intricate histories, and lots of canine populations disappeared during evolution3-6. Thus, ancient genomes from canine fossils are in high demand to clarify canine evolution and the processes leading to dog domestication. Canine transmissible venereal tumor (CTVT), the oldest known somatic cell line, is a living fossil, originating from cancer cells transmitted from a host to other canids during the mating process7. Clonal origin analyses hints that the original dog infected with CTVT (CTVT founder) came from an ancient sled dog or wolf population ...

evolutionary biology↗