African and African diaspora families that were torn apart through the Transatlantic Slave Trade are reuniting!!
When first generation Africans, such as Ghanaian immigrants or Nigerian nationals, engage in autosomal genetic genealogy testing with a company such as AncestryDNA or 23andMe, the vast majority of the genetic matches provided by the company are people of African descent, especially African Americans. Through genetic genealogy company features, genetically matched relatives are able to contact one another. So…when a person from the Congo identifies and contacts their extra-extended African American cousin, for instance, the African American cousin could learn of their specific ancestral Congolese family history and get to know their living Congolese relatives!!
Okay, so here is how reunions are possible!!
In TAKiR projects, the essential task is to identify persons within a genetic genealogy consumer database who are related to African participants in the project. We follow six steps to identify relatives.
1 To obtain genetic information, TAKiR uses the resultant DNA profile produced by a major genetic genealogy company for each person who submits a saliva sample. The DNA profile is uploaded to GEDmatch Genesis. The DNA profile contains the Reference SNP cluster ID (rsID), chromosome and position of allele, and the values of the allele pair for 700,000 single nucleotide polymorphisms (SNPs).
2 To identify relatives within the consumer database, we use several tools within GEDmatch Genesis. The first tool is Phasing which compares the DNA datafiles of the target person, their father’s DNA file, and their mother’s DNA file to create two phased DNA profiles. Although computational methods are improving, family-based phasing is the only certain why to align the alleles in the DNA profile by biological parent. One phased profile will be DNA segments shared between the target person and the mother. The other phased profile will be the DNA segments shared between the target person and the father.
3 Each phased profile is used in GEDmatch Genesis’ one-to-many comparison to provide a list of unphased consumer profiles that are genetic matches with the participants’ phased profile. Matching DNA segments share 7 cMs at minimum.
4 Matching segments are visualized in GEDmatch Genesis using the 3D chromosome browser. This tool provides a matrix comparing all selected DNA profiles from the one-to-many comparison to each other. Each selcted profile will match the participant parent-offspring phased profile. In the 3D chromosome browser results, we look for pairs of profiles also matching each other at a minimum of 3400 cMs, indicating another parent-offspring pair (or twins).
5 GEDmatch Gensis’ one-to-one comparison tool is then used to confirm that all four profiles match each other on an overlapping segment. The one-to-one comparison tool provides the chromosome, start and end location, amount of shared DNA in cMs, and number of shared SNPs for each shared DNA segment between two entered profiles. Both profiles in the participants’ parent-offspring pair are compared to both profiles in the second parent-offspring pair newly identified within the GEDmatch Genesis database. This is to confirm that all four members of the two parent-offspring pairs match each other on an overlapping segment of DNA.
6 After identifying a new parent-offspring pair who genetically match the participant parent-offspring pair, we contacted the manager of the new parent and offspring profiles by email using the contact information that they provided in GEDmatch Genesis. The initial contact email provides matching information, project information, and contact information for their ancestral (extra-extended) relative in Ghana. The TAKiR participants are also notified.
Emerging African transnational families consisting of ancestral family members are new contexts for human and community development.
Once testers identify genetically matched relatives, they are able to engage in on-going social interactions. Some connect through Facebook, WhatsApp, or email. Some have even met each other in person in their African ancestral homeland!
Happy Family Reunion!!