Can a MyHeritage DNA Test Reveal Decades-Old Family Secrets?
Using a DNA test to reveal decades-old family secrets is fascinating. However, doing so might not always be fun, sometimes it could be hurtful. Nevertheless, the gain clearly seems to outweigh the "pain" as many people are still interested in and are constantly digging out their family secrets via DNA tests. Therefore, it is no more news that DNA tests can reveal family secrets.
As reported by one of the most famous publications, USA Today, DNA is basically the key to unraveling the mysteries of your family. It reveals where a family is likely to originate from; thus, their early exposure to diseases and ailments. The revelations from such findings can prepare you for certain unexpected events in your life. A DNA test conducted using commercial DNA test kits provided by companies like MyHeritage unveils family secrets that seemed to have been buried for more than five decades.
Types of DNA tests
The family secrets revealed will depend on the type of DNA tests. The type of tests can be classified according to the location where the DNA is "harvested" from, the cell structure, or the number of markers (the number of variations being examined). Therefore, there are Y-chromosome testing, mitochondrial testing, and Autosomal testing. The Y chromosome testing can be called the Y-DNA test, Mitochondrial testing as mtDNA, while autosomal DNA can be referred to as the Single nucleotide polymorphism (SNP) test. The autosomal DNA test emphasizes the DNA location, while the SNP emphasizes the number of markers.
Y chromosome testing
The DNA in the Y-chromosome is packed in the human cell nucleus. It is passed from father to son. Therefore, only a male child can inherit these variations or markers. Despite the fact that ancestry information can only be explored by the direct male line, a female descendant can conduct the Y-DNA test by a male proxy; the male could be a sibling or relative. Like family surname, Y-chromosome are passed from one male in the family to another. Thus, it can be used to check if two or more families are related. Because Y-chromosome is passed from father to son almost unaltered, it is possible to trace your ancestry to a specific haplogroup. Haplogroup is a group of alleles that are inherited from a single parent. Therefore, it is even possible to trace yourself back to your ancestors who have lived as far as thousands of years ago if they share common genetic characteristics.
mtDNA (Mitochondrial) test
However, mitochondria is another cell component or structure that equally houses DNA; the DNA found in this region is called mitochondrial DNA. Unlike the Y-chromosome, it is passed from a mother to her offspring irrespective of their sex. Therefore, the information that can be "harvested" from mtDNA testing is about the mother's ancestry line. Your mtDNA test results can be matched with another in a database to determine if you share the same maternal ancestry.
Statements like "I'm Italian on my father's side and Hispanic on my mother's side" are credited to both Y-DNA and mtDNA test results. Like Y-DNA tests, mtDNA could reveal your ancestry to haplogroup thousands of years ago. Some experts have asserted that mtDNA can trace one's ancestry farther than the Y-DNA test. The reason for this argument is that it has been found that all humans share the same female ancestor called the mitochondrial Eve. She is believed to have lived in Africa about 150,000 years ago. It is from her direct line that different haplogroups have emerged.
Autosomal DNA/Single nucleotide polymorphism
Autosomal DNA resides in the 22 pairs of chromosomes that are not linked to sex. Therefore, it contains segments of DNA you share with every one of your relatives. For every new generation, the autosomal DNA regroup, and the offspring has a set of chromosomes from each parent. The inherited chromosomes are shared equally from both parents and almost down to the 3x great-grandparents. An autosomal DNA test is also called SNPs since it examines a large number of variations called markers or SNPs in your chromosomes. The number of these variations decreases in each successive generation. For instance, while you might inherit an equal number of SNPs from your parents, you would inherit 1/4th of these markers from each grandparent and 1/8th from each great-grandparents' parents (Should this just be great-grandparents?). As the pairing and sharing reach distant ancestors, 3x great grandparents, the markers become random and unequal. Therefore, you can't trace your ancestry to any haplogroup, unlike Y-DNA and mtDNA tests. Nevertheless, autosomal or SNP can provide comprehensive test results. For instance, it can reveal that your ancestry is 50% English, 20% Scandinavia, 15% Italian, 10% North African, and 5% unknown.
Conclusion
The DNA test, irrespective of the type, is not a Crystal ball that reveals your ancestry under the electronic microscope. Commercial DNA tests companies rely on their databases before results can be generated. For instance, MyHeritage boasts of having data on different groups from 2,114 geographic regions. Based on the test sample the company harvests from the DNA test kits of its clients, the results would be then run through the company database. If a match is found, an evaluation is then conducted. However, the results of a DNA test done by a company are only as good as their database. Furthermore, this database is again only as good as the information provided. Nevertheless, for now, most of the feedbacks on commercial DNA tests companies has not been about the integrity of the test but rather about the fun, enlightenment, benefits, and pain it brings. Most reports are found in anecdotes from periodicals like New York Posts, USA Today, and BBC News.
References:
https://nypost.com/2018/08/11/ancestry-tests-are-revealing-shocking-family-secrets/
https://www.bbc.com/news/stories-46600325
https://www.usatoday.com/story/tech/2019/07/04/is-23-andme-ancestry-dna-testing-worth-it/1561984001/
https://medlineplus.gov/genetics/understanding/dtcgenetictesting/ancestrytesting/
https://en.m.wikipedia.org/wiki/Genealogical_DNA_test
https://pubmed.ncbi.nlm.nih.gov/23612573/
https://www.myheritage.com
