Cynthia's Interests

The world as it unfolds - told from an African American woman's perspective...

Thursday, March 10, 2005

African Ancestry -

I had my DNA tested by African Ancestry (; this company was founded by African Americans - Rick Kittles, PhD., and Gina Page (from my understanding she helped with the seed money to start the company).

Anyway, I always yearned to know what part of Africa my ancestors came from. Rick Kittles developed two tests that can trace African Americans maternal and paternal lineages back to their original ancestors using either a matri-clan or patri-clan test. The matri-clan test analyzes an individual mitochondrial DNA, which is passed from mother to child (males or females) whereas the patri-clan test analyzes the Y chromosome, which is passed from father to son. Since I aleady know my fathers' Y chromosome came from his Jewish grandfather, I decided to trace my mother's lineage by buying the matri-clan test ($350). Using the mitochondrial DNA one can trace your mother's, mother, mother, mother's ancestry - all the way back to the first African female in your lineage that was stolen and enslaved by Europeans. This is exciting news: I can find my very own Mitchondrial Eve - "The First Woman"....

Before, I disclose the results of the test, I will give a brief description of mitchondrial DNA. The mitochondria are subcellular organelles that serve as sites for the production of energy. Mitochondria contain their own independent genome called mtDNA composed of 16,569 nucleotide pairs that do not recombine because it is inherited intact from your mother. As a result, mtDNA provides a historical record that contains information about maternal ancestry.

Moving right alone, my results are rather interesting. Since I was using my mitochondrial DNA, it should have ultimately lead me to the tribe of my "Mother Eve". Instead, my mitochondrial DNA inherited from my mother who was utimately inherited from the First Eve (African Mother) is closely related two groups: The Mende people in Sierra Leone and the Kru people in Liberia. What this suggests is that there was a common ancestor between the two groups. I hypothesize that a single woman had at least two daughters that married into different families. One migrated to Sierra Leone and the other stayed in Liberia or vice verse. To my surprise, instead of being related to only one group, I'm extremely lucky and fortunate to be related to two different groups. Two for the price of one (Twofer). It is unfortunate that these two countries have been ravaged by civil unrest/wars. I am certainly looking forward to visiting both places soon.

Dr. Kittles analyzes or reads the mtDNA. His company analyzes a portion of your mitochondrial DNA sequences called the Hypervariable Segment I region (HSVI), which is a non-coding portion of your mtDNA.

FYI- as a general rule, unless people are talking about your immune system, when you hear people talking about variable portions of DNA, you can automatically assume the region(s) do not code for proteins (this could lead to a disease state in some people or even death, unless it confers some type of selective benefit to the individual(s) such as what is seen in some Africans and Middle Easterners - one sickle cell allele (Hemoglobin S). Inheriting one sickle allele automatically confers resistance to malaria, which is a good thing, where as if an individual inherites two sickle allele -the outcome is early death. This happened to one of my first cousins. He died by the time he was either 6 or 7 years old.

His lab analyzes approximately 360 base pairs of DNA using polymerase chain reaction (PCR). There are specific primers that can be purchased that will allow him to amplify the specified region (HSVI) and then sequence the DNA, i.e. break it down to its' simplest components. The simplest components are called base pairs and they are represented by the letters A, C, T, and G, which allows him to easily decode the DNA sequences and catalog the results. Where the majority of humans may have one base pair (or letter); there are a small number of humans that have a different base pair at the same position. The scientific term for these differences or mutations are called single nucleotide polymorphisms. Polymorphisms is a fancy way of saying many forms. Those differences tell scientist something unique about the ancestry of one group vs. the next. Dr. Kittles then reads these mutations and compares them to sequences complied in his African Lineage Database (ALD). This database was complied mostly from West Africans and a few other historically known African groups where people were stolen from and enslaved in the Americas, etc..

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