Loan Nguyen has a Ph.D. in molecular/animal genetics (2018) and is currently a Research Fellow at the Centre for Animal Science, Queensland Alliance for Agriculture and Food Innovation, at the University of Queensland. Her research focuses on understanding how genetics influences livestock production and reproductive biology, using innovative genomic technologies. Her current work is developing an epigenetic aging clock and creating unique digital identifiers for cattle.

Birth dates are typically unknown or inaccurate in extensively grazed cattle production systems. Here, we derived the first epigenetic clock for tropically adapted cattle using Oxford Nanopore Technologies' MinION, from tail hair, a tissue that is widely used in industry for genotyping. Cattle (n = 66) with ages ranging from 0.35 to 15.7 years were sequenced and methylation was called. Sites were then filtered and used to calculate a covariance relationship matrix based on methylation state. BLUP was used with 10-fold cross validation to predict age. The correlation between predicted age and actual age was 0.71 for all sites and 0.60 for dog/human sites. The mean absolute deviation was 1.4 years for animals aged less than 3 years of age.