Genetic ancestry of African-Americans reveals new insights about gene expression

Dec 05, 2008

The amount of proteins produced in cells—a fundamental determinant of biological outcomes collectively known as gene expression—varies in African American individuals depending on their proportion of African or European genetic ancestry. These findings, by researchers based in Boston, Philadelphia and Oxford, are published December 5 in the open-access journal PLoS Genetics.

Gene expression is known to vary among individuals and to be influenced by both genetic and environmental factors. Previous studies have reported gene expression differences among human populations, but it has been suggested that this could be due to non-genetic effects. Populations of recently mixed ancestry such as African Americans, who on average inherit about 80% African and 20% European ancestry, offer a solution to this question, since individuals vary in their proportion of European ancestry while the analysis of a single population minimizes non-genetic factors.

In this study, the researchers show that gene expression levels in African Americans vary as a function of each individual's proportion of European ancestry. The differences due to ancestry (i.e. population differences between all Africans and all Europeans) were generally small—much smaller than differences between individuals within the same population; nevertheless, the authors were able to draw a distinction between effects of genetic ancestry at the location of the expressed gene (cis) and genetic ancestry elsewhere in the genome (trans). They conclude that only about 12% of heritable variation in human gene expression is due to cis regulation.

First author Alkes Price says, "It was a surprise that these conclusions could be drawn given that the differences due to genetic ancestry are so small." However, he cautioned that the results were confined to gene expression levels in a particular type of tissue known as lymphoblastoid cell lines, and have yet to be verified in other tissue types.

Citation: Price AL, Patterson N, Hancks DC, Myers S, Reich D, et al. (2008) Effects of cis and trans Genetic Ancestry on Gene Expression in African Americans. PLoS Genet 4(12): e1000294. doi:10.1371/journal.pgen.1000294
dx.plos.org/10.1371/journal.pgen.1000294

Source: Public Library of Science

Explore further: Research shows 'mulch fungus' causes turfgrass disease

Related Stories

Our bond with dogs may go back more than 27,000 years

May 21, 2015

Dogs' special relationship to humans may go back 27,000 to 40,000 years, according to genomic analysis of an ancient Taimyr wolf bone reported in the Cell Press journal Current Biology on May 21. Earlier genome ...

Southern Europeans have North African genes

Jun 05, 2013

(Phys.org) —Southern Europeans are more genetically diverse than Northern Europeans. Geneticists have several different explanations for this phenomenon, one of which is migration from Africa to southern ...

Recommended for you

Research shows 'mulch fungus' causes turfgrass disease

2 hours ago

Inadvertently continuing a line of study they conducted about 15 years ago, a team of Penn State researchers recently discovered the causal agent for an emerging turfgrass disease affecting golf courses around ...

Study on pesticides in lab rat feed causes a stir

4 hours ago

French scientists published evidence Thursday of pesticide contamination of lab rat feed which they said discredited historic toxicity studies, though commentators questioned the analysis.

Why the seahorse's tail is square

4 hours ago

Why is the seahorse's tail square? An international team of researchers has found the answer and it could lead to building better robots and medical devices. In a nutshell, a tail made of square, overlapping ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.