I'm interested in knowing how gentic/dna gelealogy is done.?

Question

How can dna be traced generations back as well as to specific places in the world when dna usage is only recent? How can someone tell if the company doing this is reputable? Thanks.

Answer 1

There are two different things you can do with DNA.

One is to compare the "Y" chromosone in males who are sons of sons of sons . . .. It is relatively unchanged, since we get it from our fathers. So, for instance, is Samuel Pack, 174x - 1833 is my 7th great grandfather, and we suspect Samuel's father was George Pack, (171x - 1754) of Maryland, I get my DNA tested and hope a proven (male) Pack descendant of George Pack gets his tested; if we match on 37 points, there is a 90% chance that my Samuel was a son, cousin or nephew to George.

Then we can hire a researcher in Marlyand to see if he/she can prove it through wills, deeds and so forth.

The second kind is over my head, but there are similarities between halpogroups in large racial/ethnic/geographic groups of people. I would not know a halpogroup if it bit me, but I've seen the word used.

Scientists have been looking at DNA for long enough that, given a sample, they can tell that your ancestors came from certain places. The best example of this are the African-Americans, who just know their ancestors were captured somewhere in Africa, driven like cattle to somewhere near present-day Ghana, sold to the slavers and shipped across the Atlantic. With enough tests they can find out what tribes in Africa their ancestors came from, which tells them the general area.

The company I used was a public-private venture; its partner is the University of Arizona. As in any transaction, you look at who they are associated with, how many satisfied customers they have, how long they have been in business. You might also Google things like

"Acme DNA Corp" Fraud
"Acme DNA Corp" Complaint

If you get a raft of hits, take your business elsewhere.

Here is the FAQ page for the company I used.
http://www.familytreedna.com/faq.html

Answer 2

I have noticed that on Yahoo! answers most people feel that DNA does NOT tell you where your ancestors came from, which is contradictory to the experts.
Rather than trying to persuade you, I suggest that you check these sites:
www.familytreedna.com and
https://www3.nationalgeographic.com/genographic/faqs_about.html
Family Tree is the oldest and most respected DNA testing site. I used it...
National Geographics is the world's foremost genotype program.
Both have DNA samples from hundreds of countries.
DNA is SCIENTIFIC; it relates to the human genome, which was fully interpreted only in recent years.
By the way, if was an African-American who discovered that a person's DNA tells you where they came from...An Indian's (Native American) DNA is very different from any of the folks in Asia, but more similar to an Asian than to whites or blacks.
If you want to know if the company is reputable, read up on that company. Family Tree is mentioned frequently; as well as National Geographics.
Other sources include books. I recommend "Genealogy 101" by Barbara Renick, a National Genealogical Society book. (www.ngsgenealogy.org) This book also does a good presentation of the Y dna and mtDNA.

Answer 3

All I can tell you is that FamilytreeDNA is a very good company. I took my DNA test through them, and I was hooked up with several people who are certainly my relatives. Research has proven what the DNA pointed to. See the link below:

Once you go to that website you can read about how they trace people. Also I noticed that the first answerer is also referring to FamilytreeDNA, so that might give you some idea that they are reputable.