What can an autosomal DNA test tell me about my ancestry going 4 generations back?

Question

For example, my great grandfather was listed on the census as mulatto, family history says he was Native American, and in a picture of him, albeit a black and white picture, he appears as far as I can tell white/caucasian. Would an autosomal DNA test be able to tell me of what ancestry he was, assuming that the rest of my ancestry is European? I know that chromosomes are inherited differentlt by different descendants, so would it better advised to test my mother and uncle(grandchildren of my great-grandfather) to get better results?

Answer 1

I tend to defer to others about DNA testing.. because I have not used, or studied the specifics of it.  Although, in this case, I'll add a bit of my info.  I agree that the tests normally will not show what persons often expect.

However, there is a way that it can be directly used in genealogy, which is when it is COMPARED with testing from other persons WHEN THOSE OTHER PERSONS HAVE THE SAME SURNAME.  This happens in direct male lines (which would happen if your uncle carries down his grandfather's name).  Many families have gotten together to form projects, in which they already have paper info to support their connection, AND the DNA tests are used to verify.

For example, 4 persons all carry the name Clements, and 3 of those lines have found records to show they are sons of John Clements.  The 4th group believes they descend from John, but have not located proof.  By testing someone of all 4 lines (the more the better), they often can show enough in the dna markers to "prove" that they descend from a common ancestor. Let's say another line has made an error in their research, and thinks they descend from John.. in that case, the testing will show that they do NOT share close enough dna (or none at all).

Since your focus is on gr grandpa, in this instance, I'd personally believe that it would be better to test uncle, ESPECIALLY if he happens to carry the surname (he is a direct male line).  And I would investigate if there currently is a cooperative DNA project going on, involving that name/family.

I currently am in and out of answers, so if you will send me a note through my profile with the name/place of great grandpa, I will run a search for such a project.

Answer 2

Tebs is correct. His answers are very thorough.  It will not tell you specific countries but Haplogroups.

Autosomal is better since most of your DNA is autosomal and you get it 50-50 from both parents, but I don't know if it would be specific about different family lines.  Y DNA is passed soley from father to son.  Mitochondrial is passed from mother to both sons and daughters but only the daughters pass it on to their children.   If you are male you can get both a Y & Mitochondrial test but it would not give you the DNA of the spouses in all your direct male line or direct female line.

Answer 3

A Dna test for ancestry cannot tell you which race people in any particular generation were, but it can tell which specific races are in your lineage, female mtdna will only show her female line, Y-Dna is only passed on through the male line, and it is the Y-Dna which is used for the type of test you are talking of. I have added below, an answer I have given to previous questions, it might also help you.

Human cells contain 23 pairs of chromosomes: 22 pairs of autosomes, and one pair of s*x chromosomes. Females carry a pair of X chromosomes that can swap, or recombine, similar regions of DNA during meiosis. However, males harbor one X chromosome and one Y chromosome, and significant recombination between these dissimilar s*x chromosomes does not occur. Therefore, the non-recombining region of the Y chromosome (NRY) remains largely unchanged over many generations, directly passed from father to son, son to grandson, and so on, along with genetic variations in the NRY that may be present. Scientists can use genetic variations, such as single nucleotide polymorphisms (SNPs), on the Y chromosome as markers of human ancestry and migration.

It is very effective and the best companies will retest until they get a conclusive result.

If you have, say, just the first 12 markers tested($149 with FTDNA), that will give an indication of where you originated, the more markers you test on, the more information is gained ( for mtdna, your suggested geographic origin and your maternal deep ancestral ethnic origin, $129 with FTDNA) if you test on the maximumum of, say 67 markers ($349 with FTDNA), it is possible then to find a match to someone else carrying your own, or a different surname, and to prove a link where perhaps no "paper trail" exists. It can therefore pinpoint a place in which your ancestors probably lived in recent history but DNA does not, obviously, have a surname attached to it, surnames have only been used for around 700 years and of course your DNA originated 10s of thousands of years ago, so there will be a great many people who have exactly the same Y-DNA, because because they all descend from the one man in whom the mutations occured to form your specific haplogroup, but again, they will not all have the same last name.

You can also have a SNP test which will help show the migratory pattern of your ancient ancestors. You can join a Surname project, in your name, or a variant of you name. (e.g. with FTDNA) and receive discounted prices on your tests.

I recommend that you make yourself aware of the various tests available, and the costs with each testing company.

Plus, check out what is available to you after you have tested.

I used Family Tree DNA ,they were the first in the field (founded in 1999), have the largest data base, and do the testing for the National Geographic's Genome project, their "after sales" is excellent and I consider they are the best, but you have to make your own decision on that.

http://www.familytreedna.org

NOTE :-

If you are female, you only carry your mother's Mtdna, and her mother's Mtdna, and her mother's Mtdna etc.,etc.,etc. and that will show only your mother's lineage (you will pass that Mtdna on to your daughters and sons, but your sons will not pass it on to their children). You do not inherit your father's Y-DNA.

If you are male, you inherit your father's Y-DNA, his father's Y-DNA, his father's Y-DNA, and so on back to your origin. You also inherit your mother's Mtdna, but you only pass your Y-DNA on to your sons.

As a female, if you use your dna for the Mtdna test, you can only test for your maternal line. If you have a brother, his dna can be used to test for both,you mother's Mtdna and your father's Y-DNA. from the one sample.

If you are male, your Y-DNA is the same as your paternal great grandfathers, so you would not need to use your uncle's Y-DNA. If you are female you can use the Y-DNA of your father, brother, or uncle, because they all have the same Y-DNA.