Purging of deleterious burden in the endangered Iberian lynx
Deleterious mutations continuously accumulate in populations, building up a burden that can threaten their survival, particularly in small populations when inbreeding exposes recessive deleteri ous effects. Notwithstanding, this process also triggers genetic purging, which can reduce the deleterious...
| Autores: | , , , , , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2022 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/289591 |
| Acceso en línea: | http://hdl.handle.net/10261/289591 |
| Access Level: | acceso abierto |
| Palabra clave: | Genetic load Purging Small populations Population genomics Conservation |
| Sumario: | Deleterious mutations continuously accumulate in populations, building up a burden that can threaten their survival, particularly in small populations when inbreeding exposes recessive deleteri ous effects. Notwithstanding, this process also triggers genetic purging, which can reduce the deleterious burden and mitigate fit ness inbreeding depression. Here, we analyzed 20 whole genomes from the endangered Iberian lynx and 28 from the widespread Eurasian lynx, sister species which constitute a good model to study the dynamics of deleterious mutation burden under con trasting demographies, manifested in the consistently smaller pop ulation size and distribution area of the Iberian lynx. We also derived analytical predictions for the evolution of the deleterious burden following a bottleneck. We found 11% fewer derived alleles for the more putatively deleterious missense category in the Iberian lynx than in the Eurasian lynx, which, in light of our theoretical predictions, should be ascribed to historical purging. No signs of purging were found in centromeres nor in the X chro mosome, where selection against recessive deleterious alleles is less affected by demography. The similar deleterious burden levels for conspecific populations despite their contrasting recent demo graphies also point to sustained differences in historical popula tion sizes since species divergence as the main driver of the augmented purging in the Iberian lynx. Beyond adding to the ongoing debate on the relationship between deleterious burden and population size, and on the impact of genetic factors in endan gered species viability, this work contributes a whole-genome cat alog of deleterious variants, which may become a valuable resource for future conservation efforts. |
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