Study challenges evolution of FOXP2 as human-specific language gene

August 2, 2018, Cell Press
First author Elizabeth Atkinson extracts DNA as part of her research on human gene FOXP2. Credit: Elizabeth Atkinson

FOXP2, a gene implicated in affecting speech and language, is held up as a textbook example of positive selection on a human-specific trait. But in a paper published August 2 in the journal Cell, researchers challenge this finding. Their analysis of genetic data from a diverse sample of modern people and Neanderthals saw no evidence for recent, human-specific selection of FOXP2 and revises the history of how we think humans acquired language.

"A paper published in 2002 (Enard et al., Nature 418, 869-872) claimed there was a selective sweep relatively recently in human evolutionary history that could largely account for our linguistic abilities and even help explain how modern humans were able to flourish so rapidly in Africa within the last 50-100,000 years," says senior author Brenna Henn, a population geneticist at Stony Brook University and UC Davis. "I was immediately interested in dating the and re-analyzing FOXP2 with larger and more diverse datasets, especially in more African populations."

Henn says that when the original 2002 work was done, the researchers did not have access to the modern sequencing technology that now provides data on whole genomes, so they only analyzed a small fraction of the FOXP2 gene in about 20 individuals, most of whom were of Eurasian descent. "We wanted to test whether their hypothesis stood up against a larger, more diverse dataset that more explicitly controlled for human demography," she says.

FOXP2 is highly expressed during brain development and regulates some muscle movements, aiding in . When the gene isn't expressed, it causes a condition called specific impairment in which people may perform normally on cognitive tests but cannot produce spoken language. FOXP2 has also been shown to regulate language-like behaviors in mice and songbirds.

"In the past five years, several archaic hominin genomes have been sequenced, and FOXP2 was among the first examined because it was so important and supposedly human specific," says first author Elizabeth Atkinson of Stony Brook University and the Broad Institute of Harvard and MIT. "But this new data threw a wrench in the 2002 paper's timeline, and it turns out that the FOXP2 mutations we thought to be human specific, aren't."

Atkinson and her colleagues assembled mostly publicly available data from diverse human genomes—both modern and archaic—and analyzed the entire FOXP2 gene while comparing it to the surrounding genetic information to better understand the context for its evolution. Despite attempting a series of different statistical tests, they were unable to replicate this idea that there was any positive selection occurring for FOXP2.

"FOXP2 is still a textbook example taught in every evolutionary biology class despite the recent data from archaic DNA," says co-author Sohini Ramachandran, an evolutionary and computational biologist at Brown University. "So while we're not questioning the functional work of FOXP2 or its role in language production, we're finding that the story of FOXP2 is really more complex than we'd ever imagined."

The researchers hope that this paper will serve as a template for other population geneticists to conduct similar projects on human evolutionary history in the future.

"We're interested in figuring out, on a genetic level, what makes us human," Henn says. "This paper shows how important it is to use a diverse set of humans in studying the evolution of all of us as a species. There's a severe Euro-centric bias in a lot of medical and other scientific studies, but we've found a scientific impetus for emphasizing diversity and inclusivity in data collection because it clearly yields more accurate results."

Explore further: Evolving genes lead to evolving genes

More information: Cell, Atkinson et al.: "No evidence for recent selection at FOXP2 among diverse human populations" http://www.cell.com/cell/fulltext/S0092-8674(18)30851-1 , DOI: 10.1016/j.cell.2018.06.048

Related Stories

Evolving genes lead to evolving genes

April 18, 2013
Researchers have designed a method that can universally test for evolutionary adaption, or positive (Darwinian) selection, in any chosen set of genes, using re-sequencing data such as that generated by the 1000 Genomes Project. ...

Recommended for you

A single missing gene leads to miscarriage

October 19, 2018
A single gene from the mother plays such a crucial role in the development of the placenta that its dysfunction leads to miscarriages. Researchers from the Medical Faculty of Ruhr-Universität Bochum (RUB) have observed this ...

Making gene therapy delivery safer and more efficient

October 18, 2018
Viral vectors used to deliver gene therapies undergo spontaneous changes during manufacturing which affects their structure and function, found researchers from the Perelman School of Medicine at the University of Pennsylvania ...

Student develops microfluidics device to help scientists identify early genetic markers of cancer

October 16, 2018
As anyone who has played "Where's Waldo" knows, searching for a single item in a landscape filled with a mélange of characters and objects can be a challenge. Chrissy O'Keefe, a Ph.D. student in the Department of Biomedical ...

Researchers use brain cells in a dish to study genetic origins of schizophrenia

October 16, 2018
A study in Biological Psychiatry has established a new analytical method for investigating the complex genetic origins of mental illnesses using brain cells that are grown in a dish from human embryonic stem cells. Researchers ...

Why heart contractions are weaker in those with hypertrophic cardiomyopathy

October 16, 2018
When a young athlete suddenly dies of a heart attack, chances are high that they suffer from familial hypertrophic cardiomyopathy (HCM). Itis the most common genetic heart disease in the US and affects an estimated 1 in 500 ...

Importance of cell cycle and cellular senescence in the placenta discovered

October 15, 2018
Working with researchers from Stanford University and St. Anna Children's Cancer Research, researchers from Jürgen Pollheimer's laboratory at the Medical University of Vienna's Department of Obstetrics and Gynecology have ...

0 comments

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.