據(jù)PhysOrg網(wǎng)站2006年8月16日報道,,本周,包括澳大利亞聯(lián)邦科學(xué)與工業(yè)研究組織(CSIRO)和新西蘭農(nóng)業(yè)研究協(xié)會在內(nèi)的國際研究組織的科學(xué)家完成了?;蚪M測序的大部分工作,,這項成果使科學(xué)家改善牛類健康和疾病控制、提高牛肉和奶制品營養(yǎng)價值的能力大幅提升,。
據(jù)介紹,,新的全基因組序列包含了29億個堿基對,這比以前版本的?;蛐蛄卸嗔巳种灰陨?。除測序工作以外,科學(xué)家對這些堿基對的差異性,,即單核苷酸多態(tài)性(SNPs)也進行研究,。堿基對的差異可以影響一個基因的功能,決定牲畜產(chǎn)量的高低,。作為一種基因標記,,對2百多萬種的單核苷酸多態(tài)性進行研究也是此項基因測序工作的一部分。
該項研究得到美國5300萬美元的資助,,澳大利亞聯(lián)邦科學(xué)與工業(yè)研究組織博士羅斯•特拉姆是“?;蚪M序列項目”的澳大利亞代表。他說,,“我們可以用這些數(shù)據(jù)來對那些與牛哺乳,、繁殖、肌肉生長,、生長率和疾病抵御等重要功能相關(guān)的基因進行鑒別,。新的牛基因圖標志著基因測序階段的工作已經(jīng)接近尾聲,,現(xiàn)在主要任務(wù)就是對有用數(shù)據(jù)進行分析,。這是一個非常重要的消息。在今后50年的時間里,,我們將在牛畜飼養(yǎng)和生產(chǎn)方面取得長足進步,,我們將結(jié)束持續(xù)了8000年的傳統(tǒng)畜牧模式”。
牛遺傳學(xué)家們將用?;蚪M作為一個模板進行同類牛群和不同類牛群之間,,以及牛與其它類型哺乳動物之間遺傳變異的研究,。
澳大利亞聯(lián)邦科學(xué)與工業(yè)研究組織家畜業(yè)生物信息研究帶頭人布賴恩•達爾利姆普勒認為,新的?;驍?shù)據(jù)非常有價值,,因為它能為研究人員提供一個更加完善的牛基因圖譜,,幫助研究人員修改脫氧核糖核酸代碼以獲得想要的產(chǎn)品特性。達爾利姆普勒說,,“我們可以使用這些數(shù)據(jù)來對那些與牛哺乳,、繁殖、肌肉生長,、生長率和抗病性等重要功能相關(guān)的基因進行鑒別”,。
赫里福種食用牛(Hereford breed)被選定為此項基因排序工程的樣品牛,此項工程起始于2003年12月份,??茖W(xué)家還對荷爾斯坦牛、安格斯牛,、澤西種乳牛,、利姆辛牛、挪威紅牛和婆羅門牛的基因進行了排序,,以鑒定這些不同種類牛之間的特殊遺傳差異性,。
達爾利姆普勒博士說,“這只是我們制造動物和食物革命的開端,。一旦我們擁有一套完整的基因,,比如能影響肉嫩度的基因,我們將來就能對一種特定類型的動物喂養(yǎng)特定類型的草料或者谷物,,使它們能始終長出特定標準的嫩肉和像大理石花紋一樣肥瘦相間的肉”,。他說,盡管幾個世紀以來一直進行的同系繁殖創(chuàng)造出了不同的品種,,但是這種繁殖保持了“巨大”的遺傳差異性,。
基因組數(shù)據(jù)可以通過許多公共數(shù)據(jù)庫獲得,包括貝樂醫(yī)學(xué)院人類基因組測序中心數(shù)據(jù)庫 (http://www.hgsc.bcm.tmc.edu,),;美國國家衛(wèi)生研究院生物技術(shù)信息中心的GenBank數(shù)據(jù)庫 (http://www.ncbi.nih.gov/Genbank,),;歐洲分子生物學(xué)實驗室測序數(shù)據(jù)庫 EMBL Bank (http://www.ebi.ac.uk/embl/index.html,);日本DNA數(shù)據(jù)庫 (http://www.ddbj.nig.ac.jp,),。
部分英文原文:
Completed genome set to transform the cow
Developed by an international consortium of research organisations, including CSIRO and AgResearch New Zealand, the new bovine sequence contains 2.9 billion DNA base pairs and incorporates one-third more data than earlier versions.
Differences in just one of these base pairs (known as single nucleotide polymorphisms or SNPs) can affect the functioning of a gene and mean the difference between a highly productive and a poorly performing animal. Over two million of these SNPs, which are genetic signposts or markers, were identified as part of the project.
“We can use this data to identify those genes that are involved in important functions like lactation, reproduction, muscling, growth rate and disease resistance”Australia’s representative on the US $53 million Bovine Genome Sequencing Project, CSIRO’s Dr Ross Tellam, says the new map marks the end of the sequencing phase of the project, with the focus now on analysing the available data.
“This is very valuable information,” Dr Tellam says. “We could potentially achieve as much improvement in cattle breeding and production in 50 years as we have over the last 8000 years of traditional farming.”
Cattle geneticists will use the bovine genome as a template to highlight genetic variation within and between cattle breeds, and between cattle and other mammal species.
The head of bioinformatics research at CSIRO Livestock Industries, Dr Brian Dalrymple, says the new data is very valuable because it provides researchers with a more complete picture of the genes in a cow and how variations in the DNA code influence desirable production traits.
“We can use this data to identify those genes that are involved in important functions like lactation, reproduction, muscling, growth rate and disease resistance,” Dr Dalrymple says.
The Hereford breed was selected for the bulk of the sequencing project, which began in December 2003. Holstein, Angus, Jersey, Limousin, Norwegian Red and Brahman animals were also sequenced to detect specific genetic differences between breeds.