The President's Pen - July 2024
Focusing on autosomal DNA (atDNA), Beth explained that we receive 50% from each of our parents but siblings may not receive the exact same segments because they are handed down randomly. Even identical twins can have slight variations in their DNA due to minor mutations while gestating. The farther back we venture on our family tree, the amount of DNA passed down reduces by half, until by the fourth or fifth generation we are receiving minuscule amounts.
We documenters of family history started with microfilm, dove into dusty cabinets filled with crumbling documents, ventured into online census records, became computer genealogy savvy, and now we are wading – more like diving headfirst – into the scientific aspect of all things genealogy . . . DNA. I know that I am getting ahead of myself when starting a report with the final statement from our speaker, Beth Swartz, but it seemed important to reinforce her words, “DNA doesn’t lie!” Your DNA results not only speak to your origins, but they also link you to everyone you are related to, whether they are known to you or are a complete surprise.
Beth also explained what centimorgans (cM) are and how they contribute to locating unknown relationships or confirming known ones. Basically, the higher the number of centimorgans the closer the relationship. We can use our cM results as a way to guide our genealogical research and find new links in our family tree and build our DNA communities.
Using Ancestry.com as her focus, Beth walked us through the different aspects of atDNA findings, including Ethnicity Estimates, DNA Communities, ThruLines, and the various types of trees available: public, private, private and unsearchable, and unlinked. One of the key points she made was that the results you receive are potential ancestors, because the information is based on other people’s research, not just your own. Think of these potential ancestors as a starting point or guide; you still need to prove your findings with detective work. As for ethnicity estimates – or origins – the keyword is estimates, and these can and will change over time as more and more people send in DNA samples and expand the database.
DNA technology is a powerful tool that can enhance our understanding of what it means to be related. You can use it to solve family mysteries, expand your knowledge of where your people came from, look for new avenues to search, and discover new branches of your family tree. Take advantage of the DNA sales, test and upload your results between several websites, and invite your family members to participate, because you can never have too much data!