Sunday, March 29, 2015

Genetic Genealogy of Irish, Scots, and Scots-Irish


There are several firms that do DNA testing for individuals and groups doing genealogical research as well as research concerning ethnicity and genetic characteristics.   It has developed into a huge and profitable business.  We chose Family Tree DNA Ltd., whose headquarters are in Houston, Texas, because they are user friendly and have the largest number of participants in their data base.  In 2000, Family Tree DNA was founded by Bennett Greenspan and Max Blankfeld.  It was the first company dedicated to direct to the consumer DNA testing for genetic genealogy and family history research.  For surname studies, the Y chromosome (Y-DNA) test is used.  Surnames are handed down through the paternal line making Y-DNA testing the perfect tool for paternal ancestry research because this DNA material is only passed from father to son. For this reason only men can participate in the test.  The results are classified by haplogroup and haplotype.

Haplogroups are the major branches of the Y-chromosome tree. They are defined by Single Nucleotide Polymorphisms (SNPs) which have accumulated over many generations as the Y-chromosome is passed from father to son. These SNPs map the paths back to the single common male ancestor from which all from that group descend.  Haplogroups are mainly used for anthropological and deep ancestry research because the time frames are usually prior to the adoption of surnames.  Haplogroups are useful for researchers who are studying human migration patterns and have archeological value.  They can also be used to study tribal groups in early European history.  In layman’s terms, this data can tell you if you are a Celt, Viking, Anglo-Saxon, or if your ancestors spent the last Ice Age in Iberia.

The Y-DNA haplotype is used for genetic genealogy.  It deals with a more recent time frame relating to one’s ancestor and all the men that descend from him during the time when surnames were coming in use.   One’s father, grandfather, great-grandfather and so on, all carry the same Y chromosome DNA.  All the males that descend from the same forefather will have the same or very similar Y-DNA. Once a man tests his Y-DNA, all the other men that have tested who also descend from that common male ancestor will show up as a match in the DNA results.  When a Y-DNA haplotype match group is located the next step is genetic genealogy.

Genetic genealogy compares the haplotypes of two or more people that are a Y-DNA match to determine the degree of genetic relationship between their respective lines.  The closeness of the match, or distance, gives an indication of the time to the shared paternal ancestor.  At this point, other factors become important such as having the same or similar sounding or meaning surname, or a surname’s clan connections, or the geographic location of a match. All these factors help to determine if two related lines are of genealogical interest.  Many families triangulate with members of their match group to fill in gaps, or smash through brick walls, to add to their family’s genealogy and locate members of their family still in the old country.  An example of this; let us say Y-DNA testing confirmed that three families, that did not previously know they were related, actually share a paternal kinship dating to circa 1700.  Family A might have part of the story, and then match Family B which has more of the story, which matches Family C still in Ireland which has even more of the story.  When the stories of Family A, B, and C are put together, often a complete shared family history and genealogy are revealed.  In the case of many Irish and Scottish families, both surname and non-surname matches are important because surnames were not fixed until the early modern era in parts of Scotland and Ireland.  Members of the same clan that share paternal ancestry may not share the same surname, but in the primary sources it is often possible to discover a group of surnames linked to a paternal line.  Y-DNA haplotype testing allows primary sources from families in your match group to be used with confidence since paternal kinship has been confirmed. 

The actual process of starting a project is simple.  You go online to the Family Tree homepage, exchange emails with their contact people and in a matter of minutes you will have DNA Project up and running.  Next, order your DNA test via credit card.  The test itself is also easy to do.  You have two sterile cotton swabs with which you take a tissue sample from the inside of your mouth by rubbing your inner cheek.  This procedure is done twice 24 hours apart.  The samples are placed in sealed containers which are mailed back to the lab and some four to six weeks later you receive your results via an email message.

2 comments:

Unknown said...

Is there any way to do genetic genealogy for women usng dna? I don't have any living male to get dna from.

Sharon Curtis-September said...

Is there any way to do genetic genealogy for women usng dna? I don't have any living male to get dna from.