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bioRxiv · 10.64898/2026.01.13.699302

The landscape of structural variation in coppery titi monkeys (Plecturocebus cupreus)

Versoza, C. J.·Bales, K. L.·Jensen, J. D.·Pfeifer, S. P.
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Abstract

Coppery titi monkeys (Plecturocebus cupreus) are an important non-human primate model for studying neurobiology and social behavior, in part owing to their relatively unusual combination of social monogamy and paternal care. Despite this importance, relatively little is known regarding the underlying population genomics of this platyrrhine. This study presents high-coverage, whole-genome sequencing data from 26 individuals which, combined with a highly accurate multi-algorithm ensemble approach, was used to characterize the first map of structural variation in the species. This novel genomic resource includes over 13,000 structural variants, with the majority (>90%) being copy number variants. While many of these were found to be located in intergenic regions, several affected genes associated with disease, including an inversion predicted to impact a pathway implicated in early-onset Parkinsons disease. Furthermore, utilizing parent-offspring trios included within this study, the de novo structural variant rate was estimated to be one in every 1.5 births, similar to that reported in rhesus macaques but considerably higher than that observed in large human cohorts, as may be expected from underlying differences in life history traits amongst these species. Taken together, these insights into the structural variant landscape of P. cupreus will not only improve their utility as a behavioral model system, but will also contribute to our general understanding of the role of structural variation in both the evolution of the primate clade and disease-outcomes.

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Versoza, C. J., Bales, K. L., Jensen, J. D., Pfeifer, S. P.. 2026-01-14. The landscape of structural variation in coppery titi monkeys (Plecturocebus cupreus). https://doi.org/10.64898/2026.01.13.699302

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