21 August 2020

U.S. Slave Descendant Genetics

Welcome back. Black Lives Matter has stirred the call for reparations. Although the case for reparations for slavery is easily justified economically, socially and morally, the U.S. has failed to take any action. And a 2019 Gallup poll found Americans were opposed to cash payments to Black Americans who were descendants of slaves.

Americans’ views on cash reparations for slavery (from

It’s difficult to consider offering cash to so many Americans for something that happened centuries ago. Maybe the focus should be on reparations for wrongs done under the “Jim Crow” laws that legalized racial segregation from the post-Civil War era until 1968. These laws marginalized African Americans, denying the right to vote, hold jobs, get an education or other opportunities. The effects of redlining neighborhoods for denial of services and discriminatory housing practices, banned years ago, are still felt today.

But this is a post about slavery, not reparations. I thought you would be interested in a study that added genetic data to the historical records of the transatlantic slave trade--the forced displacement of more than 12.5 million men, women and children from Africa to the Americas between 1515 and 1865. 

Canoe used in West Africa to transport slaves from the coast to the transatlantic vessel; canoes could carry 200 slaves in their bottom, 1849 (from slavevoyages.org/resources/images/category/Vessels/2).
Adding Genetics
23andMe, Inc., the consumer personal genetics company, coupled genetic data of more than 50,000 people with transatlantic records from the Slave Voyages database, which catalogs dates, disembarkation-embarkation ports, along with a wealth of information about each voyage.

The slave decks and instruments used to chain the slaves on the Vigilante, a French slave ship that carried 345 slaves, 1822 (from slavevoyages.org/resources/images/category/Vessels/1).
The researchers found the genetic evidence was generally consistent with historical records. Most enslaved people arriving in Latin America were deported from one or two slave-trading regions; those arriving in the U.S. and British Caribbean were from all regions of Atlantic Africa.

There were inconsistencies, and these were addressed with additional historical accounts. For example, overrepresentation of Nigerian ancestry in parts of the Americas is explained by the intra-American slave trade from the British Caribbean. Underrepresentation of Senegal and Gambia ancestry across the Americas is supported by accounts of high mortality of children in transit and of Senegambians taken to rice plantations, often rife with malaria.

African Female Sex Bias
Inconsistencies of lower African ancestry and higher African female sex bias were attributed to socioeconomic factors, non-African male admixture and inhumane treatment.

More than 60% of enslaved people brought to each region were male, yet ancestry estimates revealed a bias toward African female. The study found between 4 and 17 African females for every African male contributing to the gene pool in Latin America and 1.5 to 2 African females for every African male contributing to the gene pool in British-colonized Americas.

The Americas-wide sex-bias can be attributed to generations of rape of enslaved African women by slave owners and other sexual exploitation. Regional differences may be due to higher mortality of enslaved men in Latin America as well as to racial whitening, marrying women with lighter-skinned men to produce lighter-skinned children. The lower African female sex-bias in former British colonies may be due to the practice of coercing enslaved people to have children to maintain the workforce, especially near the abolition of the transatlantic slave trade. Segregation could be a factor in the U.S.

Wrap Up
The researchers conclude, While transatlantic records have told us a large part of the story, insights from this study in combination with other historical accounts shed light on details of the genetic impact of the transatlantic slave trade on present-day populations in the Americas.

They hope the study will help the millions of people whose ancestors were forced from Africa to the Americas to better understand where their ancestors came from and what they had to endure.

Thanks for stopping by.

Example articles on reparations:
Gallup Poll on cash reparations for slavery: news.gallup.com/poll/261722/redress-slavery-americans-oppose-cash-reparations.aspx
Jim Crow Laws: www.history.com/topics/early-20th-century-us/jim-crow-laws
Reparations focused on Jim Crow Laws, including redlining:

Genetics study of slave trade in American Journal of Human Genetics: www.cell.com/ajhg/fulltext/S0002-9297(20)30200-7
Articles on study on EurekAlert! and CNN websites:
Slave Voyages website: slavevoyages.org/

No comments:

Post a Comment