Comparative single-cell RNA sequencing brain atlas of larval Astyanax mexicanus surface and Pachón cavefish

Linking specific transcriptional variations to observable traits can reveal the genetic basis of adaptive trait evolution and disease. To link genetic variation to phenotypic differences, we constructed the first single nucleus RNA sequencing (snRNA seq) brain atlas in a uniquely suited model system, the Mexican tetra Astyanax mexicanus.

We made comparisons between surface and cavefish A. mexicanus morphs, which despite having dramatically different life histories, physiologies, and morphologies, can nevertheless interbreed. Here we show a suite of genetic changes that underlie specific differences in phenotypes, including synaptic and neural rewiring, as well as circadian dysregulation between surface and cave-dwelling morphs that may underlie human sleep disorders.