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bioRxiv · 10.1101/2024.12.26.630369

Ectopic gene conversion causing quantitative trait variation

Pfalz, M.·Naadja, S.-e.·Shykoff, J. A.·Kroymann, J.
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Abstract

Why is there so much non-neutral genetic variation segregating in natural populations? We dissect function and evolution of a near-cryptic quantitative trait locus (QTL) for defense metabolites in Arabidopsis using the CRISPR/Cas9 system and nucleotide polymorphism patterns. The QTL is explained by genetic variation in a family of four tightly linked indole-glucosinolate O-methyltransferase genes. Some of this variation appears to be maintained by balancing selection, some appears to be generated by non-reciprocal transfer of sequence, also known as ectopic gene conversion (EGC), between functionally diverged gene copies. Here we elucidate how EGC, as an inevitable consequence of gene duplication, could be a general mechanism for generating genetic variation for fitness traits.

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Pfalz, M., Naadja, S.-e., Shykoff, J. A., Kroymann, J.. 2024-12-26. Ectopic gene conversion causing quantitative trait variation. https://doi.org/10.1101/2024.12.26.630369

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