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We are happy to facilitate DNA testing for our clients in order to answer certain genealogical questions.
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- A test kit to gather a cheek swab sample. This will be sent from a reputable laboratory via U.S. Postal Mail and will then need to be mailed directly back to the laboratory.
- Within approximately three weeks, you will receive the results packet from the laboratory.
- The results packet will list any possible matches with the tested DNA within the laboratory’s database.
- Legacy Tree will help to interpret the results of your test, search additional databases for possible matches, and correlate the information with your existing research and documentation. Additional research may be ordered, if desired.
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Y-CHROMOSOME (Y-DNA) PATERNAL LINEAGE DNA TEST ($380)
MITOCHONDRIAL DNA (mtDNA) MATERNAL LINEAGE DNA TEST ($380)
PATERNAL & MATERNAL LINEAGE DNA TEST ($560)
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Also available: Paternity, Sibling and Grandparent testing. Please contact us for information.
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If you require the results of your test to be admissible in court for a legal case, the samples must be collected by a health care professional under a strict chain of custody protocol. Please call us for more information if you require court admissible testing. For more information about DNA testing and its uses in genealogical research, please read the article below.
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DNA + GENEALOGY = GENETEALOGY
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We can thank Megan Smolenyak for coining the term “genetealogy” to describe the fairly recent use of genetics to expand our family trees. Testing, or more accurately, typing an individual’s DNA allows us to compare his or her DNA to another individual’s sample and determine if the two people are closely genetically related. This article will discuss the basics of using DNA testing in genealogical research.
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DNA is short for deoxyribonucleic acid which is found in the cells of every living organism. The structure of DNA is called a double helix. The column in the center of the DNA double helix contains bases or nucleotides which are arranged in pairs. The four bases are:
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Adenine (A)
Thymine (T)
Cytosine (C)
Guanine (G)
A is always paired with T, and C is always paired with G. The particular order of the letter bases arranged along the double helix form a DNA sequence, or a gene.
Back to high school again. You might remember from your biology class that traits (such as hair and eye color) are determined by genes. Genes are sections of DNA which carry specific sequences instructions to build amino acids, which in turn build proteins, which build the organism. The complete set of DNA instructions for making an organism is called its genome.
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A chromosome is a section of the DNA that carries the genes of an organism in a linear order. The nucleus or center of nearly every human cell contains a set of 46 chromosomes, arranged in pairs. We inherit one chromosome for each pair from each of our parents.
Remember the bases or nucleotides - A, T, C, and G? The bases are found along the DNA in various combinations and sequences. A sequence of bases at a particular location in the DNA sequence is called a marker. When a sample of DNA is analyzed, the scientist can compare the sequence found at a marker from one individual with the same marker of a second individual. The scientist will also find that these four bases are placed in patterns, for example GA [CTA] [CTA] [CTA] [CTA] [CTA] [CTA] GT. These repeating patterns are another factor that the scientist compares between DNA samples. From generation to generation, small changes occur in the patterns, called mutations, which distinguish an individual’s DNA from his ancestor’s.
Within the chromosome, along the strand of DNA, are the gene sequences which have identifiable functions (like determining your inherited hair or eye color, or your big feet). In between these genes are sections called junk DNA. The junk DNA are the sequences which do not have identifiable functions within the organism that is the human body. However, it is the junk DNA that carries the information used to analyze “genetealogical” relationships. Genetic information for inherited diseases is carried only in the specific genes, which means that the samples of DNA used for genealogical testing are not capable of providing personal information that some people are concerned about.
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So Who’s My Daddy’s Daddy’s Daddy?
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While we have come a long, long way from George Mendel’s discovery of the gene in 1865, genetealogy still has a long way to go. Comparing the DNA samples from two or more individuals allows the scientist to approximate how far back in time the two individuals had a common ancestor (MRCA = Most Recent Common Ancestor). Some tests can be a bit more specific, determining paternity or siblingship, but the tests of most use to genealogists are all dependent on two things:
1) The participation of and contribution of samples by individuals to the DNA databases.
2) Good, solid, old-fashioned paper trail documentation of family lines.
In other words, in order to find a match in the DNA database, someone with matching DNA has to have contributed a sample to the database in the first place. And, without the documentation to accompany a supposed DNA pedigree, it’s not worth much more than you paid for the DNA test.
That being said, DNA testing is providing clues to help solve pedigree problems and bringing cousins together every day. The more people who contribute to the growing databases of DNA samples, the higher the chance that you will find a match – whether it happens now or somewhere down the road.
These are the tests that are currently of interest to genealogists:
Autosomal DNA (atDNA) is the random combination of all genetic information passed down to us from all our blood-line ancestors. These are the merged set of randomly shuffled chromosomes we receive from our parents that determine our unique identity and appearance. There are 44 autosomal chromosomes arranged in 22 pairs numbered 1-22 from the largest set to the smallest set. Although autosomal testing can suggest the percentage of your ancient ancestral background (50% European, 25% East Asian, 12.5% Native American, and 12.5% Sub-Saharan African, for example), the tests are not very reliable, and most major testing laboratories do not currently offer them.
Y chromosome DNA (Y-DNA) is found in the Y chromosome which only exists in males. The Y chromosome is passed from male to male, and unlike other chromosomes, is not “shuffled” between generations. The Y chromosome also does not mutate very often. This means that a single DNA sequence is passed down for many generations largely unchanged, which allows us to trace a paternal line back in time.
The Ychromosome test can be used:
• To determine whether two or more men share a common male ancestor, typically by predicting the MRCA (Most Recent Common Ancestor). This is especially useful when two men share the same or a similar surname and want to identify the common ancestor.
• To trace human evolution, track migration patterns and relatedness in groups of people. Geneticists and anthropologists have analyzed and sorted human Y-DNA into about two dozen distinct major categories called Haplogroups, based on the very ancient ancestry of these groups.
• To answer paternity questions.
Mitochondrial DNA (mtDNA) is a small DNA molecule inside the cells of all of a mother’s children, both male and female. Mitochondria is received from the egg cell of our mother, meaning only females can pass on mtDNA to their children. The mtDNA molecule is much shorter than the Y-DNA molecule, which means there are fewer sequences available to analyze. MtDNA mutates more frequently than Y-DNA. The Mitochondria DNA sequence is compared to a standard reference called the Cambridge Reference Sequence (CRS). If a female test subject finds a close match to another individual, it means that they probably shared a common ancestor many hundreds or even thousands of years ago. For this reason, it is usually not very helpful in determining more recent female relationships. The mtDNA test is generally used to study long-term population developments such as human migrations.
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A typical DNA test kit comes in the mail, containing two swabs that look a little like tooth brushes. There are no needles or blood samples involved. The subject uses the sterile swabs to rub gently on the inside of the cheek for about 30 seconds, which gathers the DNA cells from saliva. The swabs are then placed in a sterile container and mailed back to the lab.
Depending on the type of test you have ordered, the Y-DNA strand will be analyzed by identifying a number of markers, usually 12, 25, 37, 43, or 67. Each marker will have a numerical value determined (sometimes by the number of repeats of the sequences of those A, T, C, and G patterns). The value of each marker can then be compared to the same marker of another individual’s sample. If the series of numbers are exactly the same, or if only one or two of the markers are off by one number, the two men probably share a common ancestor within the past 500 years. If the numbers are exactly the same, and the two individuals have the same surname, the common ancestor may be as recent as the past five generations.
Geneticists estimate that between 2 and 5 percent of each generation will experience an unexpected negative match, meaning that many or all of the markers do not match. The two subjects may even be determined to belong to different haplogroups meaning there is not a common ancestor for thousands of years. These negative matches can be caused by:
• Research error – the documentation and paper trail are incorrect.
• Hidden adoptions.
• Non-paternity event – the assumed father was not the biological father of the child.
• Surname change – for some reason a family chose to change their surname.
DNA testing is an amazing technology that promises to become more and more useful in tracing a family’s history. The key is not only continued progress by the scientists who study and improve the technology, but the continued growth of the databases of test results. And, just as important, accurate, documented research to support the additions of these newfound ancestors to our family’s tree.
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We'd love to help you discover your family tree! Send us your genealogy questions for a free consultation.
Click here to see what clients have to say about our work.
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What do clients have to say about our work?
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What is the process you can expect when you order research through Legacy Tree Genealogy?
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Legacy Tree is headquartered near the Family History Library in Salt Lake City, Utah, the largest genealogical library in the world. We also order records through agents all over the globe.
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