研究在新冠病毒中發現新的基因突變。這一發現有什麼意義？
For a virus, spreading for a few months and reaching more than 3 million hosts is a long time span to evolve and change.
傳播數月並感染300多萬人足以讓一種病毒進化、改變。
Some viruses - like influenza - mutate a lot, meaning that we need to update vaccines yearly to remain on top of the spread of seasonal flu. Meanwhile, the coronavirus that has caused the current COVID-19 pandemic has stayed relatively stable, and it seems to be mutating much more slowly than influenza.
流感等病毒發生了很多變異，我們需要每年更新疫苗來控制季節性流感的傳播。同時，導致本次疫情的冠狀病毒一直相對穩定，好像比流感的變異速度慢得多。
This is great news for vaccine development and for the scientists who are closely studying the virus. But that doesn't mean it's not mutating at all.
這對疫苗研發和仔細研究這種病毒的科學家來說是個好消息，但並不意味着病毒就一點都沒有發生突變。
Two new studies have recently been released analysing SARS-CoV-2 mutations. One study, from Arizona State University, discovered a large DNA deletion in a virus sample taken from a patient in Tempe.
最新發布的兩項新的研究分析了新冠病毒的突變。其中亞利桑那州立大學進行的研究在從坦佩市一位病人體內採集的病毒樣本中發現了一大段DNA缺失。
The second study, currently still a pre-print from the Los Alamos National Laboratory, tracked mutations throughout the outbreak, and hypothesised that one strain of the virus is more infectious than the original Wuhan strain.
另外一項研究目前還只是洛斯阿拉莫斯國家實驗室的預印本，這項研究在整個疫情期間追蹤突變，研究人員猜測有一種病毒比武漢的原始病毒傳染性更強。
The Arizona study generated three full-length SARS-CoV-2 genomes from a series of samples; they found that one of these genomes, which they've named AZ-ASU2923, had a large deletion - 81 DNA base pairs - in a gene called ORF7a.
亞利桑那州的研究從一系列樣本中獲得了三個新冠病毒全長基因組，他們將其中一個命名爲AZ-ASU2923，發現它的ORF7a基因有81個DNA鹼基對的一大段缺失。
The ORF7a gene creates an accessory protein, which helps the virus infect, replicate and spread inside the human host. Specifically, the protein is thought to help the virus to evade our immune system and kill the cell once the replication process is complete.
ORF7a基因產生輔助蛋白，幫助病毒在人體內感染、複製和傳播。具體說來，這種蛋白質被認爲能幫助病毒避開我們的免疫系統，一旦完成複製就會殺死細胞。
"One of the reasons why this mutation is of interest is because it mirrors a large deletion that arose in the 2003 SARS outbreak," says one of the researchers, virologist Efrem Lim from Arizona State University.
亞利桑那州立大學的病毒學家Efrem Lim 也是其中一位研究人員，他說：“這種突變很重要的一個原因是它和2003年爆發非典時出現的大段缺失很像。”
Right now, we don't know how this mutation would change the coronavirus, and the researchers are investigating. Past research on similar genes and the fact it's only been found in a single individual, suggest that this deletion probably isn't great news for the virus.
目前我們不知道這種突變會對冠狀病毒有什麼影響，研究人員正在對此進行調查。過去對類似基因進行的研究和只在一個人身上發現這種情況的事實說明，這種缺失對病毒來說可能不是一個好消息。
