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In 2025 scientists recovered the oldest RNA yet, from Yuka, a young woolly mammoth frozen in the Siberian permafrost for nearly 40,000 years, and saw which genes were active in its muscles.

Cell (2025)

ScienceNature

The story behind the card

DNA is the full instruction book found in almost every cell. RNA is the working copy a cell makes when it actually uses a gene, so it shows what the body was doing at a given moment. RNA falls apart quickly after death, and before this study the oldest sequenced came from a canine frozen about 14,000 years ago. A team led from Stockholm University, writing in Cell, read RNA from Yuka's muscle. It showed muscle genes at work and signs of stress, possibly linked to an attack Yuka is thought to have suffered before dying. It also revealed that Yuka, long thought to be female, was male.

Türkçe oku
Sibirya'da yaklaşık 40.000 yıl donmuş kalan genç bir yünlü mamuttan, Yuka'dan, 2025'te bugüne dek okunmuş en eski RNA elde edildi. Bu RNA, hayvanın kaslarında hangi genlerin çalıştığını gösterdi.
Cell (2025)

DNA, hemen her hücrede bulunan eksiksiz bir talimat kitabıdır. RNA ise hücrenin bir geni gerçekten kullandığında çıkardığı çalışma kopyasıdır; bu yüzden vücudun o anda ne yaptığını gösterir. RNA ölümden sonra hızla dağılır; bu çalışmadan önce dizilenen en eski RNA, yaklaşık 14.000 yıl önce donmuş bir köpekgilden geliyordu. Stockholm Üniversitesi öncülüğündeki bir ekip, Cell dergisinde yayımlanan çalışmada Yuka'nın kas dokusundan RNA okudu. Sonuçlar kas genlerinin çalıştığını ve strese işaret eden izleri gösterdi; bu stres, Yuka'nın ölmeden önce uğradığı düşünülen bir saldırıyla ilgili olabilir. Aynı veriler, uzun süre dişi sanılan Yuka'nın aslında erkek olduğunu da ortaya çıkardı.

Sources and further reading

Background reading: Woolly mammoth
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