Great Migration Left Genetic Legacy
大迁移的基因馈赠

Reseachers have started to examine the genetic traces of the movement of some six million African-Americans from the south to the north and west between 1910 and 1970.
研究者已经开始检测了大约六百万非裔美国人移动的基因轨迹，这些人在1910年至1970年间从美国南部迁徙至北部或西部地区。

撰文/播音：埃里卡·贝拉斯(Erika Beras)
翻译：杨枭
审校：丁可含

It’s called the Great Migration—the journey of some six million African-Americans from the rural south to northern and western cities between 1910 and 1970. The cultural impact of the Great Migration has been well documented. But researchers have also started to look at its genetic implications. The most recent study finds that the migration had a significant effect on genomic diversity across the nation. That work is in the journal PLOS Genetics. [Soheil Baharian et al, The Great Migration and African-American Genomic Diversity]
在1910至1970年间，大约六百万非裔美国人从南部乡村迁往了西北部城市，史称“大迁移”。大迁移对于文化的影响已被充分记录在案。但研究者现在开始观察它的遗传影响。最近的研究发现，迁徙对于全国的基因多样性有重要的影响。这项工作发表在了《PLOS Genetics》上。

To estimate patterns of ancestry, researchers analyzed genetic data from nearly four thousand African-Americans who had participated in three medical studies.
为检测祖先的行为模式，研究人员分析了近四千名非裔美国人的基因数据，这些人全都参与了三项医学研究。

Their findings confirmed historical records—genetic evidence showed that female slaves often gave birth to children fathered by white slaveowners. The genetic analysis found that 82.1 percent of the average African-American’s ancestors came from Africa, while 16.7 percent were Europeans and 1.2 percent were Native American.
基因证据确认了历史记载——女性奴隶会与白人奴隶主生孩子。基因分析显示，非裔美国人的祖先中8.2%是非洲人， 16.7%是欧洲人，1.2%为美国原住民。

The team also could date when particular genes entered the mix. Native American genes were introduced into the typical African-American genome in the early 1600’s. Genes from Europeans were for the most part introduced in the decades before and during the Civil War.
该研究团队还能够对特定基因的融合鉴定年代。在17世纪早期，美国原住民的基因开始融入典型非裔美国人的基因组中，而欧洲人的基因多半是在内战及此前的几十年融入的。

Researchers also found those still living in the southern United States have a greater percentage of African ancestry than those in the north or west. And European-Americans who now live in the south are more genetically similar to African-Americans in the north and west than they are to African-Americans currently living in the South—because Blacks with a greater percentage of European ancestry were more likely to move, especially early in the migration’s history.
研究人员还发现，那些住在美国南部的人相比于北部及西部的人，基因中有更高比例的非洲血统。而且，南部的欧洲裔美国人在基因上更接近现今住在北部西部地区而不是南部的非裔美国人，因为那些有更高比例欧洲血统的黑人迁移的可能性更大，尤其是在移民时代早期。

The analysis has implications for medical research and treatment. Most of the people in studies linking genes and disease have been white, thus potentially leaving gaps in medical information specific to other races. Filling in those gaps, along with better access to medical care, could help reduce the disparity in health experienced by many minority communities.
分析结果对医学研究和治疗都有影响。在基因疾病相关的研究中人群大多为白人，这可能在其他种族特有的医疗信息中留下空白。填补这些空白以及更好地获得医疗服务，提高少数族群的健康水平。