Novel epigenetic age estimation in wild-caught Gulf of Mexico reef fishes

Cutting-edge DNA methylation-based epigenetic aging techniques were applied to Gulf of Mexico northern red snapper (Lutjanus campechanus; n = 10; 1–26 years old) and red grouper (Epinephelus morio; n = 10; 2–14 years old). Bisulfite-converted restriction site-associated DNA sequencing was used to identify CpG sites (cytosines followed by guanines) that exhibit age-correlated DNA methylation, and species-specific epigenetic clocks developed from 100s of CpG sites in each species showed strong agreements between predicted and otolith-derived ages (r2 > 0.99 for both species). Results suggest epigenetic age estimation could provide an accurate and efficient approach to mass-aging fishes in a non-invasive manner.