Age estimation using methylation-sensitive high-resolution melting (MS-HRM) in both healthy felines and those with chronic kidney disease

Age is an important ecological tool in wildlife conservation. However, it is difficult to estimate in most animals, including felines — most of whom are endangered. Here, we developed the first DNA methylation-based age-estimation technique — as an alternative to current age-estimation methods — for two feline species that share a relatively long genetic distance with each other: domestic cat (Felis catus; 79 blood samples) and an endangered Panthera, the snow leopard (Panthera uncia; 11 blood samples). We measured the methylation rates of two gene regions using methylation-sensitive high-resolution melting (MS-HRM). Domestic cat age was estimated with a mean absolute deviation (MAD) of 3.83 years. Health conditions influenced accuracy of the model. Specifically, the models built on cats with chronic kidney disease (CKD) had lower accuracy than those built on healthy cats. The snow leopard-specific model (i.e. the model that resets the model settings for snow leopards) had a better accu...年龄是野生动物保护研究中一项重要的生态学工具。然而，多数动物的年龄估算颇具难度，猫科动物亦不例外——其中多数物种已濒临灭绝。本研究针对两种遗传距离相对较远的猫科动物，开发了首项基于DNA甲基化（DNA methylation）的年龄估算技术，作为现有年龄估算方法的替代方案：家猫（Felis catus；79份血液样本）与濒危豹属物种雪豹（Panthera uncia；11份血液样本）。本研究采用甲基化敏感性高分辨率熔解曲线法（methylation-sensitive high-resolution melting, MS-HRM），对两个基因区域的甲基化率进行了检测。家猫的年龄估算平均绝对偏差（mean absolute deviation, MAD）为3.83年。动物健康状况会对模型的估算精度产生影响。具体而言，基于慢性肾病（chronic kidney disease, CKD）家猫构建的模型，其估算精度低于基于健康家猫构建的模型。针对雪豹定制的模型（即针对雪豹重置模型参数的专属模型）具备更优异的