Genotype specific polyphenism in pea aphids is associated with reproductive trade-offs, distinct gene expression patterns and limited DNA methylation differences
Year: 2026
Type: article
Abstract: Polyphenism occurs when a single genotype produces multiple discrete phenotypes in response to environmental cues and is widespread across many animal taxa. However, the molecular mechanisms underlying polyphenic development and the associated life-history trade-offs remain poorly understood. We hypothesized that environmentally induced changes in DNA methylation are associated with altered expression of genes involved in polyphenic development. Using two different pea aphid ( Acyrthosiphon pisum ) lineages that differ in their life history and polyphenic response to crowding, we found that the two genotypes showed divergent phenotypic responses to crowding: N127 produced a high proportion of pale morphs, whereas N116 preferentially produced winged morphs. Crowding-induced morphs also produced fewer offspring than their corresponding non-crowding induced morphs. Furthermore, the F 1 offspring produced by these morphs (N116 winged and N127 pale), also produced fewer offspring than the F 1 offspring produced by the corresponding non-crowding induced morphs (N116 wingless and N127 red). We further examined the expression and DNA methylation of 14 candidate genes associated with stress responses and polyphenic development. While 12 genes were differentially expressed between morphs in at least one genotype, only four genes ( Dmap1 , Rpd3 , Hsp83 and Mad) also showed significant differences in DNA methylation. These findings suggest that the different polyphenic responses of the two genotypes are associated with distinct patterns of candidate gene expression, whereas DNA methylation differences were comparatively limited and were not consistently associated with differences in gene expression.
Source: Scientific Reports
Language: English
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,690
OpenAlex ID: W7225748738