Mixed Race Studies

Skin pigmentation is far more genetically complex than previously thought

Broad Institute
Massachusetts Institute of Technology, Cambridge, Massachusetts
2017-11-30

David Cameron, Director of Communications/Media Relations

Credit : Brenna Henn South African individuals in a household that exemplify the substantial skin pigmentation variability in the Khomani and Nama populations. Picture taken with consent for publication.

By studying an African population underrepresented in most datasets, researchers find genetic complexity of pigmentation varies by latitude

Many studies have suggested that the genetics of skin pigmentation are simple. A small number of known genes, it is thought, account for nearly 50 percent of pigment variation. However, these studies rely on datasets that heavily favor northern Eurasian populations—those that reside mostly in higher latitude regions.

Reporting in the November 30 issue of Cell, researchers from the Broad Institute of MIT and Harvard, Stanford University, and Stony Brook University report that while skin pigmentation is nearly 100 percent heritable, it is hardly a straightforward, Mendelian trait. By working closely with the KhoeSan, a group of populations indigenous to southern Africa, the researchers have found that the genetics of skin pigmentation become progressively complex as populations reside closer to the equator, with an increasing number of genes—known and unknown—involved, each making a smaller overall contribution.

“Africa has the greatest amount of phenotypic variability in skin color, and yet it’s been underrepresented in large scale endeavors,” said Alicia Martin, a postdoctoral scientist in the lab of Broad Institute member Mark Daly. “There are some genes that are known to contribute to skin pigmentation, but by and large there are many more new genes that have not been discovered.”

“We need to spend more time focusing on these understudied populations in order to gain deeper genetic insights,” said Brenna Henn, assistant professor in the Department of Ecology and Evolution at Stony Brook University who, along with Martin, is a co-corresponding author…

Read the entire article here.

Being Irish, mixed race and living abroad: it’s complicated

The Irish Times
2017-12-01

Conrad Bryan, Treasurer
Irish in Britain

A scene from Hashtag Lightie, playing at the Arcola Theatre in north London.

London play ‘Hashtag Lightie’ puts the spotlight on mixed-race identity

I live in London, a melting pot of cultures and ethnicities. It is a place where anything goes and where people of different ethnicities have always mixed, loved and married.

However, today the binary black and white notion of race is being challenged by the younger generation. They are choosing for themselves where they sit on the colour spectrum and how they self-identify. No longer will they accept other people labelling them.

Many are choosing to self-identify as mixed-race rather than black, which is causing a real debate in the black community here. This has many consequences for individuals struggling to determine where they fit in society, or what side to take…

Read the entire article here.

An Unexpectedly Complex Architecture for Skin Pigmentation in Africans

Cell
Volume 171, Issue 6, 2017-11-30
pages 1340–1353.e14
DOI: 10.1016/j.cell.2017.11.015

Alicia R. Martin, Meng Lin, Julie M. Granka, Justin W. Myrick, Xiaomin Liu, Alexandra Sockell, Elizabeth G. Atkinson, Cedric J. Werely, Marlo Möller, Manjinder S. Sandhu, David M. Kingsley, Eileen G. Hoal, Xiao Liu, Mark J. Daly, Marcus W. Feldman, Christopher R. Gignoux, Carlos D. Bustamante, Brenna M. Henn

Highlights

• Skin pigmentation in Africans is far more polygenic than light skin in Eurasians
• Southern African KhoeSan populations have lighter skin compared to equatorial Africans
• Highly heritable KhoeSan skin color variation is poorly explained by known genes
• The study of African skin color identifies novel and canonical pigmentation genes

Approximately 15 genes have been directly associated with skin pigmentation variation in humans, leading to its characterization as a relatively simple trait. However, by assembling a global survey of quantitative skin pigmentation phenotypes, we demonstrate that pigmentation is more complex than previously assumed, with genetic architecture varying by latitude. We investigate polygenicity in the KhoeSan populations indigenous to southern Africa who have considerably lighter skin than equatorial Africans. We demonstrate that skin pigmentation is highly heritable, but known pigmentation loci explain only a small fraction of the variance. Rather, baseline skin pigmentation is a complex, polygenic trait in the KhoeSan. Despite this, we identify canonical and non-canonical skin pigmentation loci, including near SLC24A5, TYRP1, SMARCA2/VLDLR, and SNX13, using a genome-wide association approach complemented by targeted resequencing. By considering diverse, under-studied African populations, we show how the architecture of skin pigmentation can vary across humans subject to different local evolutionary pressures.

Read or purchase the article here.

Harry-and-Meghan is not ‘great news’ for interracial couples

gal-dem
2017-12-01

Natalie Morris

image via Vanity Fair

On Monday it was announced that Prince Harry is engaged to Meghan Markle – a half white, half black American. A mixed-race woman is about to become the first non-white member of the British monarchy, and I am conflicted.

Feelings about the Royal Family aside, my initial instinct was that the introduction of any kind of diversity to this country’s most historic institution can only be a good thing. There’s definitely a little girl inside me who wants to cry joyful tears at the thought of a black princess. But after about four minutes on Twitter and an avalanche of headlines screaming about Harry’s “exotic” choice of fiancée, I realised how this was actually going to go…

Read the entire article here.

Do Not Pass

Sunday Book Review
The New York Times
2010-02-16

Touré

This may come as a shock to you, especially if you look at whiteness as a boon and blackness as a burden, but I have never once wished to be white. If a fairy godfather came to me and said I could switch races, I’d open the window and make him use it. I think 99 percent of black people would do the same. That’s not a knock on whiteness — it seems to be working out well for many people — it’s that I love blackness, even if passing would allow me to unhook myself from the heavy anchor called racism. It’s cool: I’ve learned how to be as quick as a Br’er Rabbit, even with the anchor attached. Still, you might argue, wouldn’t switching from a disadvantaged race to the dominant one be as liberating as a winning lottery ticket? Well, for those who’ve been able to complete the sociopolitical fantasy trip and become racial transvestites, it usually ends badly.

The character who jumps the color line is a fascinating American rogue, a self-­constructed person, a trickster who’s discovered that race is not an unscalable wall but a chain-link fence with holes big enough for some people to slip through. But once they cross the line, they’re fugitives hiding in plain sight, on the lam from themselves and their histories, cut off from their families, unchained from racism but chained to a secret whose revelation would bring an end to a life built on lies and a stolen place in the dominant culture. All that makes racial shape-shifters a fantastic opportunity for a writer: they’ve got Huck Finn’s independence, an identity in turmoil, a secret that could destroy their world, a refusal to be defined by others and a vantage on race that very few ever get to have. And in the story of a racial fugitive, there’s always a ticking bomb. It’s a corollary of the literary law that if you put a loaded rifle onstage, it has to go off: if a character shifts races, eventually he’ll be unmasked, and usually it’s painful physically or psychically or both…

Read the entire article here.

A ‘people’s princess’ unbound by race

The Boston Globe
2017-12-01

Renée Graham, Associate Editor and Columnist

Meghan Markle greets wellwishers in Nottingham, England, with Prince Harry, on Dec. 1. OLI SCARFF/AFP/Getty Images

All it took for Meghan Markle to “become” black was a proposal from a prince.

“Black American Princess. Palace about to be lit,” a black woman tweeted hours after an official announcement of Markle’s engagement to Prince Harry. Another posted, “So I’ve seen a black president of the United States, and now I’ll see a black woman joining the British royal family. What a time to be alive.”

There’s just one caveat: Throughout her public life, Markle, the daughter of an African-American mother and a white father, has referred to herself as biracial or mixed-race…

Read the entire article here.

Trump Administration Delays Decision On Race, Ethnicity Data For Census

National Public Radio
2017-12-02

Hansi Lo Wang, National Correspondent

The 2010 census form included separate questions about race and Hispanic origin. The White House has yet to announce its decision on a proposal that would allow race and ethnicity to be asked in a single, combined question on the 2020 census. Paul J. Richards/AFP/Getty Images

A major decision on the way the U.S. government collects information about race and ethnicity through the census and other surveys was expected to be announced this week by the Trump administration.

But the White House’s Office of Management and Budget, which sets standards for this type of data for all federal agencies, was silent on Friday, which OMB had said was the deadline for an announcement.

A spokesperson for OMB could not provide any information about the delay.

Under consideration by the White House are proposals introduced during the Obama administration that would fundamentally change how the government counts the Latino population. Another proposal would create a new checkbox on census forms and other federal surveys for people with roots in the Middle East or North Africa. If approved, the policy changes could have significant implications on the upcoming 2020 census, as well as legislative redistricting, civil rights laws and health statistics…

Read the entire article here.