媒體英語(yǔ)會(huì)帶大家一起學(xué)習(xí) BBC 撰稿人在報(bào)道世界大事時(shí)常用到的單詞和短語(yǔ)。

一項(xiàng)研究結(jié)果顯示，遠(yuǎn)在恐龍時(shí)代出現(xiàn)的一些病毒仍然在活躍于當(dāng)代人類(lèi)的遺傳基因里。

至今為止，科學(xué)界對(duì)基因組的了解仍然處于初級(jí)狀態(tài)，科學(xué)家們希望這項(xiàng)研究能夠提供有關(guān)人類(lèi)基因淵源的線(xiàn)索。BBC 記者 David Shukman 發(fā)回了以下報(bào)道。

With only a small part of our genetic material fully understood, scientists have been trying to unravel where most of our DNA came from and what it does. Now researchers from Oxford, New York and Belgium have investigated the genes of 38 mammals – including humans, mice, elephants and dolphins, and they've found that most of them share traces of the same ancient viruses. The work has established that at least one virus infected our common ancestors as long as one hundred million years ago.

The scientists found that these micro-organisms have adapted to stay within their host cell where they have thrived. So within the double helix of our DNA lies not only a legacy of past infections but also a miniature eco-system in which the viruses live on and evolve.

The researchers hope that further work will identify what role these genetic parasites might play. There's no evidence that they cause harm, indeed one ancient virus is known to help in the growth of the placenta. According to the senior author of the study, Dr Robert Belshaw of Oxford University, understanding these survivors from the distant past may provide clues to the early detection of cancers or infections.