What does a Kittler test do?
On the Y chromosome the DSY385 marker has repeat segments in two different locations, call them site X and site Y. What a Kittler test does is identify at which location these repeats are found at.
Why do a Kittler test?
When we receive our results for the DSY385a/b markers we get they report in a low high sequence (10-14) but that is not necessarily the order that they are located on the Y chromosome. That is we do not know if the 10 was a site X or Y and consequently nor where the 14 was.
So what does that matter to the I2* groups?
In the words of Ken Nordtvedt “If a haplogroup or clade has modal 385 values close to identical, the clade haplotype population can have members today of both Kittler order, and folks with identical normal reported values at 385 could be multiple mutational steps from each other. A 12,13 at 385 could be 12-13 or 13-12. Those two real states are two normal mutations from each other. To get from one to the other there would be 12-13 mutates to 13-13 or 12-12 and then that state mutates to 13-12.”
The Modal for the 3 Major groups within I2* are Close A & C = 12/14 and B= 12/13. So knowing the correct location of these two values is important to correctly calculate the number of mutations different between two or a number of results. If you are using the “as normally reported order” for the values you could be getting an incorrect count on mutational variation from the reality that the Kittler order of the results would give.