An epigenetic clock to estimate the age of living beluga whales

摘要: Introduction: DNA methylation data facilitate the development of accurate molecular estimators chronological age, or epigenetic clocks. We present a robust clock for beluga whale, Delphinapterus leucas, developed an endangered population in Cook Inlet, Alaska, USA. Methods and Results: used custom array to measure levels at 37,491 cytosine-guanine sites (CpGs) from skin samples dead whales (n = 67) whose ages were estimated based on tooth growth layer groups. Using these calibration data, penalized regression model selected 23 CpGs, providing R2 0.92 training data; 0.74 median absolute age error 2.9 years leave one out cross-validation. applied independent set 38 collected with biopsy dart living between 2016 2018. Age estimates ranged 11 27 years. also report sex correlations CpG describe approach identifying animal using methylation. Discussion: The presented here have broad applications conservation management Inlet potentially other cetaceans.