雞在幾千年時(shí)間里的馴化及其后來向產(chǎn)肉雞和產(chǎn)蛋雞的分化，是一個(gè)可以提供關(guān)于馴化問題及基因型演化問題的很多信息的模型。

        用大型并行測序方法對家雞及其野生祖先紅原雞所做的一項(xiàng)研究，顯示了若干“選擇性片段”，在這些片段上，與一種大大增強(qiáng)存活能力的突變相的有利基因變異相對于其他等位基因在頻率上有所增加。這些變異中zui引人注目的一個(gè)（見于所有家雞），是位于為刺激甲狀腺的荷爾蒙受體編碼的一個(gè)位點(diǎn)上的變異，它在代謝及脊椎動(dòng)物生殖時(shí)間中起一個(gè)關(guān)鍵作用。

        這個(gè)片段也許與被馴化動(dòng)物的一個(gè)典型特征相關(guān)：沒有野生種群中所見的對季節(jié)性生殖的嚴(yán)格調(diào)控。在肉雞中所檢測到的幾個(gè)選擇性片段上，與生長、食欲和代謝調(diào)控相關(guān)的基因重疊在一起。

上海勁馬生物推薦原文出處：

Nature doi:10.1038/nature08832

Whole-genome resequencing reveals loci under selection during chicken domestication
Carl-Johan Rubin1,10, Michael C. Zody1,2,10, Jonas Eriksson1, Jennifer R. S. Meadows1, Ellen Sherwood3, Matthew T. Webster1, Lin Jiang1, Max Ingman4, Ted Sharpe2, Sojeong Ka5, Finn Hallb??k5, Francois Besnier6, ?rjan Carlborg6, Bertrand Bed’hom7, Michèle Tixier-Boichard7, Per Jensen8, Paul Siegel9, Kerstin Lindblad-Toh1,2 & Leif Andersson1,6

1Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, SE-75123 Uppsala, Sweden
2Broad Institute of Harvard and MIT, 7 Cambridge Center, Cambridge, Massachusetts 02142, USA
3Department of Cell and Molecular Biology, Karolinska Institutet, SE-17177 Stockholm, Sweden
4Department of Genetics and Pathology, The Rudbeck Laboratory, Uppsala University, SE-75185 Uppsala, Sweden
5Department of Neuroscience, Uppsala University, SE-75124 Uppsala, Sweden
6Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Box 597, SE-75124 Uppsala, Sweden
7INRA, AgroParisTech, UMR1313 Animal Genetics and Integrative Biology, F-78350 Jouy-en-Josas, France
8IFM Biology, Link?ping University, SE-58183 Link?ping, Sweden
9Virginia Polytechnic Institute and State University, Department of Animal and Poultry Sciences, Blacksburg, Virginia 24061-0306, USA

Domestic animals are excellent models for genetic studies of phenotypic evolution1, 2, 3. They have evolved genetic adaptations to a new environment, the farm, and have been subjected to strong human-driven selection leading to remarkable phenotypic changes in morphology, physiology and behaviour. Identifying the genetic changes underlying these developments provides new insight into general mechanisms by which genetic variation shapes phenotypic diversity. Here we describe the use of massively parallel sequencing to identify selective sweeps of favourable alleles and candidate mutations that have had a prominent role in the domestication of chickens （Gallus gallus domesticus） and their subsequent specialization into broiler （meat-producing） and layer （egg-producing） chickens. We have generated 44.5-fold coverage of the chicken genome using pools of genomic DNA representing eight different populations of domestic chickens as well as red jungle fowl （Gallus gallus）, the major wild ancestor4. We report more than 7,000,000 single nucleotide polymorphisms, almost 1,300 deletions and a number of putative selective sweeps. One of the most striking selective sweeps found in all domestic chickens occurred at the locus for thyroid stimulating hormone receptor （TSHR）, which has a pivotal role in metabolic regulation and photoperiod control of reproduction in vertebrates. Several of the selective sweeps detected in broilers overlapped genes associated with growth, appetite and metabolic regulation. We found little evidence that selection for loss-of-function mutations had a prominent role in chicken domestication, but we detected two deletions in coding sequences that we suggest are functionally important. This study has direct application to animal breeding and enhances the importance of the domestic chicken as a model organism for biomedical research.