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Personal DNA 101



Most of the time we hear about DNA test being used for paternal and land disputes. Here is the list of the aspects of DNA that are most helpful for Personal Genomics.


MTDNA:

Also known as la mama de la mama de la mama... this is not a pepito joke! Think of following the line of who was your mother's mothers' mother's mother... ad infinitum. Both male and female's have Mtdna's as the information of the Mtdna is inside the X, and nearly everyone is either X X or X Y. This prestigious line traces back to a single female ancestor on your direct maternal line. 

How far back? Well the truth is that much of the continents where relatively isolated up until 500 years ago, so there are unique signatures that only exist in certain continents. Each Mtdna starts of with a letter and is followed by a sequence of letters and numbers depending on age of each of these unique maternal mutations. 

Example: My Mtdna is L3b1a. This maternal line is found in many populations throughout west Africa, in fact all mtdnas that start with L's are of African Origin. While A's for example are of Native American and East Asian origin. 


Y-DNA:

In layman's terms what your surname is supposed to represent, your direct single male ancestor. Father of your father of your father... ad infinitum. Unfortunately this test only works on biological males because males are X Y and women are X X. If you are a femme testing do not be discouraged, if you want to find out your direct paternal ancestor, you can test a brother or a paternal uncle. 

How far back? Just as Mtdna it goes back as far back as it has unique mutations but generally its root letter is unique to a continent or region. Also like Mtdna is is starts with a letter followed by a sequence of letters and numbers.

Example: My Ydna is EV13 which is found in populations throughout southern Europe with concentrations in the Italy/Greece. However E's are native to Africa but there is a branch of E that has been in Europe for the last 15,000 years and mine is one of these. 

Autosomal DNA:

This is the contents of your Sancocho, the how much ñame vs batata vs yuka etc. Autosomal dna is everything that makes you up YOU. It is most of your ancestors crammed into 23 pairs of chromosomes. This is what the dna companies read to tell you that your this much % of this and that. 

How far back? Not all of your ancestors are visible in your dna, namely those who may have been unique and older then 500-700 years. So lets say you have a Chinese ancestor in the 1300s, chances are these dna test won't pick this up, and perhaps no dna test ever will because you only inherit 50% of your dna from each parent, and the other 50% is not inherited. If you repeat these past many generations the chances for a distant ancestor showing up in your dna decrease.

For example: My Continental Autosomal results @ Ancestry.com are. : 46% European, 42% African, 9% Native-American and 1% Middle eastern. 



Comments

  1. I appreciate how you're applying genetic genealogy into your research analysis instead of solely depending on country or nationality specific identification. I'm enjoying reading your blog.

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