Age estimation of captive Asian elephants (Elephas maximus) based on DNA methylation: An exploratory analysis using methylation-sensitive high-resolution melting (MS-HRM)

Age is an important parameter for bettering the understanding of biodemographic trends-development, survival, reproduction and environmental effects-critical for conservation. However, current age estimation methods are challenging to apply to many species, and no standardised technique has been adopted yet. This study examined the potential use of methylation-sensitive high-resolution melting (MS-HRM), a labour, time, and cost-effective method to estimate chronological age from DNA methylation in Asian elephants (Elephas maximus). The objective of this study was to investigate the accuracy and validation of MS-HRM use for age determination in long-lived species, such as Asian elephants. The average lifespan of Asian elephants is between 50-70 years but some have been known to survive for more than 80 years. DNA was extracted from 53 blood samples of captive Asian elephants across 11 zoos in Japan, with known ages ranging from a few months to 65 years. Methylation rates of two candidate..., , , # Estimation of captive Asian elephants (Elephas maximus) age based on DNA methylation: An exploratory analysis using methylation-sensitive high-resolution melting (MS-HRM)

## Description of the data and file structure

1. The raw methylation data of *RALYL* and *TET2* used in this analysis are in csv files.

This is the dataset that we used to develop the age estimation model. The '**subject ID**' represents the same individuals. In contrast, '**sample**' represents the sample collections taken over time. In addition, cells containing '**n/a**' in our dataset within the 'sample' column are samples which were sampled recently and had no define number ID at the time (please refer to the Supplementary Information on the manuscript for more details on sampling date). '**sex**' represents the sex of the individual, where F: female and M: male. '**age**' represents the chronological age of the individual at the time of sampling. '**ralyl_methylationrate_ave**' and '**tet2_methylatio...