Evidence map›Paper›PMID 41462149›Full record

ArticleScientific reports2025

Less-invasive age estimation using hair based on DNA methylation in brown bears.

Shiori Nakamura, Jumpei Yamazaki, Naoya Matsumoto, Kyogo Hagino, Hideyuki Sakamoto, Masami Yamanaka, Masanao Nakanishi, Mina Jimbo, Yojiro Yanagawa, Hideyuki Ito and 2 more

Abstract read
In one paragraph

Article in Scientific reports, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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0 citing papers in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

12 authors.

Shiori NakamuraFaculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Hokkaido, Japan.
Jumpei YamazakiFaculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Hokkaido, Japan.
Naoya MatsumotoAzabu University, 1-17-71 Fuchinobe, Chuo-ku, Sagamihara, 252-5201, Kanagawa, Japan.
Kyogo HaginoNoboribetsu Bear Park, 224 Noboribetsuonsencho, Noboribetsu, 059-0551, Hokkaido, Japan.
Hideyuki SakamotoNoboribetsu Bear Park, 224 Noboribetsuonsencho, Noboribetsu, 059-0551, Hokkaido, Japan.
Masami YamanakaShiretoko Nature Foundation, 531 Iwaobetsu, Shari, 099-4356, Hokkaido, Japan.
Masanao NakanishiShiretoko Nature Foundation, 531 Iwaobetsu, Shari, 099-4356, Hokkaido, Japan.
Mina JimboFaculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Hokkaido, Japan.
Yojiro YanagawaFaculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Hokkaido, Japan.
Hideyuki ItoKyoto City Zoo, Okazaki Hosshojicho, Kyoto, 606-8333, Japan.
Toshio TsubotaFaculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Hokkaido, Japan.
Michito ShimozuruFaculty of Veterinary Medicine, Hokkaido University, Kita-18, Nishi-9, Kita-ku, Sapporo, 060-0818, Hokkaido, Japan. shimozuru@vetmed.hokudai.ac.jp.

Funding

Japan Society for the Promotion of Science JP19K06833Japan Society for the Promotion of Science JP22K14910Japan Society for the Promotion of Science JP24KJ0304Sumitomo Foundation 200561The Inui Memorial Trust for Research on Animal Science, Japan JPMJSP2119
6 · The paper itself

Abstract

Information on chronological age is essential for exploring the life history, conservation, and management of wildlife. Recently, DNA methylation-based methods using blood or skin have been established as alternatives to the traditional tooth-based method in bear species. However, the collection of these tissues is limited to captured or dead individuals. In the present study, we established the first hair-based age estimation model based on DNA methylation levels in brown bears, aiming for future application to less-invasively obtained hair of wild individuals. We performed bisulfite pyrosequencing and measured the methylation levels of hair root DNA. The methylation levels of cytosine-phosphate-guanine sites adjacent to the genes VGF, KCNK12, and ELOVL2 were found to be correlated with age. The best age estimation model used three cytosine-phosphate-guanine sites adjacent to two genes, VGF and KCNK12, with a mean absolute error of 3.2 years and median absolute error of 2.2 years after leave-one-out cross-validation. Our method is innovative because of the simplicity of sampling and the lack of requirement to capture bears. If this method can be widely applied to hair samples obtained in the field, the age structure of wild populations can be understood, contributing to ecological research, conservation, and management of bear species.

Indexed as

AgingDNA MethylationHairUrsidaeAnimalsFemaleMaleAge estimationAgingBrown bearDNA methylationEpigenetic clockWildlife management

Identifiers

PMID41462149
PMCPMC12753630

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.