Hi Paul I don't think 167 years is way out. John Chandler's 67-marker mutation rates sum to .2243 That implies on average, a mutation every 1/.2243 = 4.46 generations, perhaps every 30 x 4.46 = 134 years if you assume 30 years per generation. So 167 years is probably stretching it a little, but it's not out of the ball-park. If I understand you correctly, you have a Sligo cousin at a GD of 4 over 67 markers. However, this cousin is at a GD of 20 from a third person whose suspected relationship with you and your Sligo cousin is unclear to me. Perhaps you could elaborate? Sandy -----Original Message----- From: dna-r1b1c7-bounces@rootsweb.com [mailto:dna-r1b1c7-bounces@rootsweb.com] On Behalf Of pabloburns@comcast.net Sent: 29 October 2011 18:19 To: dna-r1b1c7@rootsweb.com Subject: [R-M222] Age of M222 Sandy (or anyone), Since I left university 55 years ago, the math portion of my brain mas atrophied from lack of use to where I now have trouble calculating the tip for restaurant service. Consequently, I was relieved when some kind soul posted that the average for 67-marker mutations is 167 years. I am sure that the real gurus were horrified, but I see on other forums that some continue to use this mutation figure in comparisons. That might be fairly close for my Sligo cousin and me. We are at a GD of 4, which would place the MRCA at 668 ybp. But, using another example, my cousin is at a GD of 20 from from our suspected Scot (20413). At 167 years per mutation the time to their MRCA would be 3340ybp. If both are M222, then either M222 was around well back in the BC period, or they mutated separately. Am I figuring this all wrong, or is using the 167 years per mutation approach completely out of the question? Paul R1b1c7 Research and Links: http://clanmaclochlainn.com/R1b1c7/ ------------------------------- To unsubscribe from the list, please send an email to DNA-R1B1C7-request@rootsweb.com with the word 'unsubscribe' without the quotes in the subject and the body of the message