DNA

Do you have questions regarding if or how you fit into our Morrison family? A DNA test will do much to bring clarity and confirmation.  Do you already know how you fit into the family? There is still much value in being tested.  The more people who participate, the clearer the genealogical picture of our family tree becomes.  It has already proved to be of immense value to our research, and we have only just begun to see the tip of the iceberg.  The procedure is safe and private. Please consider participating – if you have any question don’t hesitate to ask!

What is Genetic Genealogy?  Genealogy is the study of one’s family tree or ancestry.  Genetic genealogy uses DNA testing in combination with traditional genealogy and historical records to determine to determine the time frame in which the two individuals shared a most recent common ancestor (MRCA).

Because each man inherits his Y-DNA virtually unchanged from his father and his father from his father and so forth, Y-DNA is the easiest DNA to use for genealogical purposes.  Unfortunately changes occur, and the DNA is not always passed intact.  These changes are called mutations.  So thanks to mutations, the Y-chromosome passed from father to son will sometimes change, and the son’s Y-chromosome might differ slightly from the father’s Y-chromosome.  It is this difference that will allow us to find out if two people are related, and how close the relation is.  There are two kinds of mutations that we are most interested in.  They are referred to as SNPs and STRs.

Note: Testing Y-DNA for Morrison-Q is limited to males (since females have no Y-DNA) with the last name of Morrison. So, if you are a male – and your mother was born a Morrison and your father was born a Smith – testing your Y-DNA would be testing for the Smith line, not the Morrison line.

Y-STR DNA

A chromosome contains sequences of repeating nucleotides known as short tandem repeats (STRs).

The number of repetitions varies from one person to another and a particular number of repetitions is known as an allele of the marker.  An STR on the Y-chromosome is designated by a DNA Y-chromosome Segment (DYS) number.  For example, a common studied DYS marker is DYS393.  DYS393 has the STR sequence known as “AGAT”.  If you see a statement that says “DYS393 = 3,” then it means that the DNA sequence, “AGAT,” is repeated 3 times like this -> AGATAGATAGAT.

Y-DNA testing involves looking at Y-STR segments of DNA on the Y-chromosome.  The STR segments which are examined are referred to as genetic markers.  These mutations can be valuable in identifying branches of a family tree.

The range of possible generations before you share a common ancestor with a match depends on the level of test you take.  A match may be recent, but it may also be hundreds of years in the past.

Y-SNP DNA

single-nucleotide polymorphism (SNP) is a change to a single nucleotide in a DNA sequence.  The relative mutation rate for an SNP is extremely low.  This makes them ideal for marking the history of the human genetic tree.  SNPs are named with a letter code and a number.  Y-SNPs are used to designate the Y-Haplogroups, the big branches of the ancient human family tree.  Each SNP refers to a mutation in which one group breaks off from the other into those that carry the mutation and those that do not.

The two main categories of researchers interested in researching Y-SNPs are deep ancestry researchers and genealogical researchers.  Deep ancestry researchers appear to be working diligently to discover new Y-SNPs and adding new branches to the Haplotree.  Surname project administrators and many active genetic genealogical researchers are working to build clusters of related lines that provide the vast majority of the data that deep ancestry researchers require for their analysis.

BIG-Y DNA Test

An alternative to individual Y-Testing is to use Next Generation Sequencing and have the Big Y-DNA done.  The major benefit of the Big Y test from FTDNA is that it will help discover and define the Y-Haplogroup tree to the point that private SNPs will define families or parts of families. Until now Y-STRs were the way to go for recent genealogy and Y-SNPs were used for ancient or genealogy back thousands of years.  These new tests, by uncovering thousands and thousands of new SNPS are bridging the time gap and will eventually map the Y-Tree with detail.

The new tests are primarily testing Y-SNPS.  One advantage SNPs have over STRs is that they happen only once (with very rare exceptions), so that everyone sharing a particular Y-SNP is related.  In the past these SNPs represented mutations that happened thousands of years ago but new technology is bringing us SNPs that may have happened in the past 100-500 years.  Many of these SNPs are considered private or semi-private.  What this means is that when a new Y-SNP is discovered it will be considered private if it does not appear in any other samples and semi-private if it appears in a small number of samples with the same surname or a low Genetic Distance.  Obviously it will take much effort to categorize SNPs properly.

If you compare Y-SNPs with Y-STRs the latter changes with much greater frequency and represents the number of repeats at a given marker.  They may pick up or drop off a repeat every now and then.  Y-STRs do not represent one time events.  It is possible that a grandfather might have 24 repeats and his grandson 23 repeats at a given marker, and then down the line a 3X great-grandson has 24 or 22.  With a Y-SNP every man bearing a particular SNP inherited it from the same man whether that common ancestor was 100 years ago or 10,000 years ago.

X-DNA (not used in test results by Family Tree DNA)

We all inherit one X-chromosome from our mothers and an X-chromosome or Y-chromosome from our fathers (Male=XY Female=XX).  It has a unique pattern of inheritance that can be useful, but X-DNA is not being explored as much as the Y-DNA for genealogical purposes.  The Family Finder test does not currently use X-Chromosome DNA (X-DNA) test results.  The X-Chromosome follows a different inheritance pattern than your autosomal DNA.  Therefore, it requires a different matching algorithm to be accurate and scientifically valid.  However, FTDNA does show X-Chromosome matching for X-DNA segments when someone is an autosomal DNA match.

Mitochondrial (mtDNA) DNA Tests

Mothers pass mtDNA to their children, both sons and daughters, but only females pass it on. Your mtDNA was inherited from your mother and from her mother and from her mother. No matter how far back in time you go, you only have one direct maternal ancestor in each generation, and she is the one responsible for passing you your mtDNA.  Your mtDNA has followed this matrilineal path down through the generations for many thousands of years intact and virtually unchanged.

A mitochondrial DNA (mtDNA) test looks at your female-inherited mitochondrial DNA.  Family Tree DNA offers three levels of mtDNA tests.

mtDNA (HVR1):  The HVR1 test will show you your basic maternal ancestry reaching back hundreds of thousands of years.  It includes testing to determine your basic mitochondrial DNA haplogroup placement.  For genealogy, this basic mtDNA test is best used to rule out a shared maternal ancestor between two people.

mtDNAPlus (HVR1&2):  The HVR1&2 test will show you your basic maternal ancestry reaching back hundreds of thousands of years.  By including the second hypervariable region (HVR2) this test is also able to provide more refined geographic origins data for your maternal line in the last 2,000 years.  Like the basic mtDNA test, the mtDNAPlus test is best used to rule out a shared maternal ancestor between two people.  The higher resolution offers greater ability to distinguish between lines.

mtDNA Full Genomic Sequence:  The mtDNA Full Sequence test is the preferred test for understanding the genealogy, historic, and ancient ancestry of your direct maternal line.  By testing the full mitochondrial genome, you will be placed in one of hundreds of mtDNA haplogroup subclades according to current published peer reviewed literature.  Each subclade has a unique migration history that traces from ancient times through more recent historic events.

Autosomal DNA (atDNA) Tests

The Family Tree DNA autosomal test is known as the Family Finder.  This test is designed to find relatives on any of your ancestral lines within approximately the last 5 generations. Family Finder uses autosomal DNA, which is the mixture of DNA you received from both parents (approximately half from each one).  Because autosomal DNA is a mixture of your mother’s and father’s DNA, it is unique to each person.  Both men and women can complete this test.  However, the test cannot distinguish between matches from your mother’s side versus your father’s side.

Links to Morrison-Q DNA Projects:

Morrison-Q Y-DNA Project

Morrison-Q Autosomal DNA Project