READING AND COMPARING RESULTS

In the chart below, results are shown for the 12 Marker test and the 37 Marker test. The same principle of analysis described below applies to the 67-marker test. The higher the number of Markers tested, the greater the resolving power of the test, which then has significant value when comparing results to others. When our scientists developed our panels of markers, they did it based on the volatility of each marker, which is an important factor. We don't want a marker that doesn't mutate at all with time, as it would yield no information of relevance: this will lead to many matches and therefore give the false impression of two individuals being related, when in fact they are not. On the other hand, we don't want a marker that is too volatile, since it will create too much confusion when trying to identify family branches. The composition of our panel of markers is one of the key factors that differentiates Family Tree DNA from other companies.

When comparing Y DNA results to others, the surname is a critical element. Depending on your ancestral country, hereditary surnames were adopted at different times. For England, most people had adopted hereditary surnames by 1400. As genealogists, we are generally not concerned with those to whom we are related prior to the adoption of surnames. The use of surnames combined with Y DNA testing sets a limit in the past for considering relationships. When a Y DNA result matches and the surname or variant matches, the two people are related since the adoption of surnames.

The combination of Y DNA test results and surnames can be applied to each Line or family tree of a surname, to determine whether there was one or multiple points of origin for the surname.

When utilizing Y DNA testing with genealogical research, a paper trail may define the relationship between individuals. By testing two individuals in a documented family tree, you can confirm the paper research when the two individuals Y DNA results match, or are a close match.

There are many applications for Y DNA testing to genealogy research. These range from the example above of confirming the paper research, to more advanced applications such as determining the number of points of origin for a surname, and finding the ancestral homeland.

When comparing the Y DNA results of two individuals, the surname must be considered. Y DNA matches with others of different surnames are most likely a result of being related prior to the adoption of surnames.

When comparing results between individuals with the same surname, there can be a variety of situations. In the chart above, the first two individuals are what is called a 12/12 match. They match each other exactly on the 12 Marker test. The third 12 Marker result on the chart does not match the other two results, and therefore it is inconclusive in terms of establishing whether there is a relationship or not.

The scientists provide estimates of the time frame for being related. These estimates depend on the number of Markers tested. The more Markers tested, and the higher the number of Markers that match, the higher the likely hood that the common ancestor occured more recently.

Examples of 37 Marker results are also shown above. There is one result which matches on 12 Markers to the other 37 Marker results, and then the balance of the result does not match closely. This result illustrates the value of testing more Markers. The time frame for relatedness for 12 Markers is much longer than the time frame for 37 and 67 Markers.

The 37/37 Marker matches and the 36/37 Marker matches with the same surname are the type of results one would expect to receive when testing closely related people with Y DNA testing. These results are then interpreted in relationship to the genealogical research and in relationship to the results of others with the same surname. The interpretation process is not difficult, and the larger the set of results, often the interpretation becomes easier.

mtDNA
Your mtDNA results will be presented in the form of a table with the mutations from the CRS (Cambridge Reference Sequence) in the HVR1, HVR2 or both. It will look like this:

Table A

The mtDNA sequence is read from left to right with the first nucleotide at position 16,001.

In order to make it easier to understand what Table A refers to we have highlighted in red one of the mutations (16264T) at the CRS Table. It represents one of the differences between this mtDNA sequence and the Cambridge Reference Sequence (CRS). A red-letter T in position 16264 shows that you have a T in place of the G listed for that position in the Cambridge sequence. In some cases you will see insertions or deletions in your mtDNA sequence. If you have an insertion after base pair 255, for example, the insertion will be listed as 255.1C. In this case a single base pair insertion has been found in your mtDNA string, noted by the .1 and the protein is Cytosine, denoted by the C. If you have a 2 base pair insertion the results will look like this: 255.1C 255.2T. It is also possible that you have a deletion, where a base pair that was not copied and you just don't have a base pair at that particular place. A deletion looks like this: 224 - . The dash signifies that the location, 224 isn't in your mtDNA sequence and is represented by a minus sign at the site where the protein should have been found.

Your analysis highlights these mutations and may be compared to other individual’s mutations. Our database will be helpful in finding other individuals with exactly the same mtDNA. This exact duplication of the mtDNA means two individuals shared a common female ancestor. Since the mutation rate of the mtDNA is much slower than the Y-DNA, the probablilities associated with the time to a Most Recent Common Ancestor in a case of perfect mach will point to a common ancestor living farther back than in the case of the Y-DNA. Research over the last decade has suggested several maternal lines ultimately all originating from the first woman “Eve” approximately 140,000 years ago in Africa.