> ----- Original Message ----- > From: "Tim Callaghan" <tim.callaghan@4hstc.freeserve.co.uk> > To: <IRL-CORK-L@rootsweb.com> > Sent: Sunday, May 14, 2006 8:41 AM > Subject: Pre-surname era > > > > I have done a Y chromosone DNA test and have found > connections like apparent ancesters with 'non-Callaghan' > surnames, presumably connected before surnames were used. > > My reading of DNA 'Y' Chromosome testing, tells me that if two individuals match exactly at all ponts in a 12 marker test, there is a 50% probability of a MRCA (Most Recent Common Ancestor) within the last 14 generations (exact value is14.4) . Now, let's assume, that a generation is 25 years, times 14.4 indicates that 360 years ago the couple had a 50% probability of having a common ancestor. What confused me was your email speculating on 'pre-surname time' connections going that date back over 900 years. **** Reply to LIST only, please. Thank you. Padraig An Sean Gabhar -- ---------------------------------------- I am using the free version of SPAMfighter for private users. It has removed 185 spam emails to date. Paying users do not have this message in their emails. Try www.SPAMfighter.com/pro for free now!

Padraig, Let me throw one more monkey wrench (spanner) into the works. We have a Johnston/e family in which the father and his two sons had their Y-DNA tested. One son is one marker away from him while the other is also a marker away, but a different marker, making the sons 2 markers away from each other - both markers are "fast changing" markers. So I have a feeling that any "dating" guidelines need to be looked at with a grain of salt. They are guidelines, not exact rules that are carved in stone... Cliff. Johnston "May the best you've ever seen, Be the worst you'll ever see;" from A Scots Toast by Allan Ramsay ----- Original Message ----- From: "Padraig Mor O'Gealagain" <padraigogealagain@rogers.com> To: <IRL-CORK-L@rootsweb.com> Sent: Monday, May 15, 2006 8:13 AM Subject: Re: Pre-surname era/ >> ----- Original Message ----- >> From: "Tim Callaghan" > <tim.callaghan@4hstc.freeserve.co.uk> >> To: <IRL-CORK-L@rootsweb.com> >> Sent: Sunday, May 14, 2006 8:41 AM >> Subject: Pre-surname era >> > >> > I have done a Y chromosone DNA test and have found >> connections like apparent ancesters with 'non-Callaghan' >> surnames, presumably connected before surnames were used. >> > > > My reading of DNA 'Y' Chromosome testing, tells me that if > two individuals match exactly at all ponts in a 12 marker > test, there is a 50% probability of a MRCA (Most Recent > Common Ancestor) within the last 14 generations (exact > value is14.4) . > > Now, let's assume, that a generation is 25 years, times > 14.4 indicates that 360 years ago the couple had a 50% > probability of having a common ancestor. > > What confused me was your email speculating on 'pre-surname > time' connections going that date back over 900 years. > > > **** Reply to LIST only, please. Thank you. > > Padraig > An Sean Gabhar > > > -- > ---------------------------------------- > I am using the free version of SPAMfighter for private users. > It has removed 185 spam emails to date. > Paying users do not have this message in their emails. > Try www.SPAMfighter.com/pro for free now! > > > > ==== IRL-CORK Mailing List ==== > Searchable archives for IRL-CORK can be found at > http://listsearches.rootsweb.com/?list=irl-cork > > ============================== > New! Family Tree Maker 2005. Build your tree and search for your ancestors > at the same time. Share your tree with family and friends. Learn more: > http://landing.ancestry.com/familytreemaker/2005/tour.aspx?sourceid=14599&targetid=5429