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J1 DYS388=13
10-10-2015, 08:03 AM
Can the age of this branch of mtDNA be estimated using the following data?

Using 16 FMS samples (which are the K1a10a C16291T block at http://www.ianlogan.co.uk/sequences_by_group/k1a10_genbank_sequences.htm )

The average number of mutations is 33.375

The Standard Deviation is 1.183

The square root of the SD is 1.0876

I don't have spreadsheet software/expertise, and I don't know how to calculate "Soares rho value."

Do I have enough information to estimate the age of this branch?

GailT
10-10-2015, 08:42 PM
Here is a link to the a page with the Soares spreadsheet. (http://www.cell.com/AJHG/supplemental/S0002-9297%2809%2900163-3)

I would calculate rho as the average of the number of extra mutations in the 16 samples, i.e., exclude all mutations that define K1a10a. I would also exclude heteroplasmies and these markers when counting the extra mutations: 309, 315, 522, 523, 16093, 16182, 18183, 16193, 16519.

edit: You might also want to exclude HQ287881 as it seems to be an older branch point between K1a10 and K1a10a. If you include only the 15 samples that share T9698C, I count 7 mutations, rho = 7/15, for an age estimate of about 1200 years for the group that shares T9698C.

J1 DYS388=13
10-11-2015, 09:44 AM
Thanks very much.

I'm finding it hard to understand how K1a10a could have spread all over Britain and Ireland within just 1200 years (your estimate) or 2700 years (Costa et al. 2013) (see yellow markers at https://www.google.com/maps/d/edit?hl=en&authuser=0&mid=z0C7lmnLIDx4.kd1FhjurwdXY )

But I guess that's a historical question, not a genetic question.