I posted the same question on the DF27 forum but then the topic is more general so I might as well reach out to a broader audience. I often see these claims like that mutations are really random: That is, any mutation is as likely as any other mutation after taking the mutation rate into account. This puzzles me a and keeps me awake! I will try to explain below:

Starting with DF27+, if I take all 1240 haplotypes from the YSTR charts, and count all the mutations, there is something I can't put together. DYS19=15 occurs in 13% of all cases, DYS392=14 occurs in 5% of all cases. There are 194 haplotypes for the first 11 markers with one 1-step mutation from the modal ("13 24 14 11-11 14 12 12 11 13 13")

Still, there is NONE with DYS392=14 (== "13 24 14 11-11 14 12 12 11 13 14") and only 3 with DYS19=15 (== "13 24 15 11-11 14 12 12 11 13 13"). Statistically that doesn't make sense, does it?

Now to be fair, in my modal example I used DYS439=11, but in reality the modal value is 12. Still, looking at the DF27+ DYS439==11 population only = 291 persons, 45 = 15% have DYS19=15 and 11 = 4% have DYS392=14, so the statistics are more or less the same wether I use all of the DF27+ population, or only those that have DYS439=11 as a starting point. If I rerun the same excercise with one 1-step mutations forcing DYS439=11, there are 86 that are 1 step away over the first 10 markers (+DYS439=11, fixed). And again, this should give 13 and 3-4 people on average with the named extra mutation, but there are only 3 and none, resp.

Maybe I am simply asking after a fact that is long known, any links to this are appreciated. Maybe this is a genetic drift of some sort? (i.e. some mutations are found more in some branches then others, others here being modal). Any feedback appreciated.

Starting with DF27+, if I take all 1240 haplotypes from the YSTR charts, and count all the mutations, there is something I can't put together. DYS19=15 occurs in 13% of all cases, DYS392=14 occurs in 5% of all cases. There are 194 haplotypes for the first 11 markers with one 1-step mutation from the modal ("13 24 14 11-11 14 12 12 11 13 13")

Still, there is NONE with DYS392=14 (== "13 24 14 11-11 14 12 12 11 13 14") and only 3 with DYS19=15 (== "13 24 15 11-11 14 12 12 11 13 13"). Statistically that doesn't make sense, does it?

Now to be fair, in my modal example I used DYS439=11, but in reality the modal value is 12. Still, looking at the DF27+ DYS439==11 population only = 291 persons, 45 = 15% have DYS19=15 and 11 = 4% have DYS392=14, so the statistics are more or less the same wether I use all of the DF27+ population, or only those that have DYS439=11 as a starting point. If I rerun the same excercise with one 1-step mutations forcing DYS439=11, there are 86 that are 1 step away over the first 10 markers (+DYS439=11, fixed). And again, this should give 13 and 3-4 people on average with the named extra mutation, but there are only 3 and none, resp.

Maybe I am simply asking after a fact that is long known, any links to this are appreciated. Maybe this is a genetic drift of some sort? (i.e. some mutations are found more in some branches then others, others here being modal). Any feedback appreciated.

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