The Genographic Project - My Genetic History

MY GENETIC SEQUENCE

Type: Y-Chromosome
Haplogroup: R1a (SRY 10831.2)

My STRs
DYS393: 13, DYS439: 10, DYS388: 12, DYS385a: 11
DYS19: 15, DYS389-1: 13, DYS390: 25, DYS385b: 14
DYS391: 11, DYS389-2: 17, DYS426: 12,DYS392: 11

How to Interpret My Results
Above are results from the laboratory analysis of my Y-chromosome. My DNA was analyzed for Short Tandem Repeats (STRs), which are repeating segments of my genome that have a high mutation rate. The location on the Y chromosome of each of these markers is depicted in the image, with the number of repeats for each of my STRs presented to the right of the marker. For example, DYS19 is a repeat of TAGA, so if my DNA repeated that sequence 12 times at that location, it would appear: DYS19 12. Studying the combination of these STR lengths in my Y Chromosome allows researchers to place me in a haplogroup, which reveals the complex migratory journeys of my ancestors. Y-SNP: In the event that the analysis of my STRs was inconclusive, my Y chromosome was also tested for the presence of an informative Single Nucleotide Polymorphism (SNP). These are mutational changes in a single nucleotide base, and allow researchers to definitively place me in a genetic haplogroup

MY GENETIC HISTORY

My Y-chromosome results identify me as a member of haplogroup R1a1.

The genetic markers that define my ancestral history reach back roughly 60,000 years to the first common marker of all non-African men, M168, and follow my lineage to present day, ending with M17, the defining marker of haplogroup R1a1.

If you look at the map, in the next blog post, highlighting ancestors' route, you will see that members of haplogroup R1a1 carry the following Y-chromosome markers:

M168 > M89 > M9 > M45 > M207 > M173 > M17

Today a large concentration—around 40 percent—of the men living in the Czech Republic across the steppes to Siberia, and south throughout Central Asia are members of haplogroup R1a1. In India, around 35 percent of the men in Hindi-speaking populations belong to this group. The M17 marker is found in only five to ten percent of Middle Eastern men. The marker is also found in relatively high frequency—around 35 percent—among men living on the eastern side of present-day Iran.

What's a haplogroup, and why do geneticists concentrate on the Y chromosome in their search for markers? For that matter, what's a marker?

Each of us carries DNA that is a combination of genes passed from both our mother and father, giving us traits that range from eye color and height to athleticism and disease susceptibility. One exception is the Y chromosome, which is passed directly from father to son, unchanged, from generation to generation.

Unchanged, that is unless a mutation—a random, naturally occurring, usually harmless change—occurs. The mutation, known as a marker, acts as a beacon; it can be mapped through generations because it will be passed down from the man in whom it occurred to his sons, their sons, and every male in his family for thousands of years.

In some instances there may be more than one mutational event that defines a particular branch on the tree. This means that any of these markers can be used to determine your particular haplogroup, since every individual who has one of these markers also has the others.

When geneticists identify such a marker, they try to figure out when it first occurred, and in which geographic region of the world. Each marker is essentially the beginning of a new lineage on the family tree of the human race. Tracking the lineages provides a picture of how small tribes of modern humans in Africa tens of thousands of years ago diversified and spread to populate the world.

A haplogroup is defined by a series of markers that are shared by other men who carry the same random mutations. The markers trace the path my ancestors took as they moved out of Africa. It's difficult to know how many men worldwide belong to any particular haplogroup, or even how many haplogroups there are, because scientists simply don't have enough data yet.

One of the goals of the five-year Genographic Project is to build a large enough database of anthropological genetic data to answer some of these questions. To achieve this, project team members are traveling to all corners of the world to collect more than 100,000 DNA samples from indigenous populations.

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