The primary objective for participating in a Y-DNA study is determine
whether you have a 'Common Paternal Ancestor' with another participate.
This page addresses how many generations back your common paternal
ancestor maybe.
Statically, mutations occur between father and son about every
twenty to twenty-five years.
One mutational difference is not considered significant, the
probability of relationship diminishes with each mutation.
Participants with 12 marker results should order the 25 marker test
to narrow down the time-frame for determining their Time to Closest
Ancestor.
Test results having an
exact match on all 12 markers, time to their
closest ancestor, can be calculated as follows:
Estimates using the Infinite Alleles
method and the standard mutation rate of 0.002 are bulleted below. This estimate was
obtained from this site
Probability distribution of time to MRCA: Y
Chromosome markers that explains in
further details how this information was calculated for test results
reflecting a 12 marker match.
They have a 50% chance of having a
common ancestor within 14 generations.
They have a 90% chance of having a
common ancestor within 48 generations.
They have a 95% chance of having a
common ancestor within 62 generations.
Estimates using the Infinite Alleles
method and a high mutation rate of 0.004 are bulleted below.
They have a 50% chance of having a
common ancestor within 7 generations.
They have a 90% chance of having a
common ancestor within 24 generations.
They have a 95% chance of having a
common ancestor within 31 generations.
Test results having a single step mutation,
their time to their
closest ancestor can be calculated as follows:
Estimates using the Infinite Alleles
method and the 0.002 average are bulleted below. This estimate was
obtained from this site
Probability distribution of time to MRCA: Y
Chromosome markers that explains in
further details how this information was calculated for test results
reflecting a 1 single step mutation.
They have a 50% chance of having a
common ancestor within 37 generations.
They have a 90% chance of having a
common ancestor within 85 generations.
They have a 95% chance of having a
common ancestor within 103 generations.
Test results having two single step
mutations, their time to their closest ancestor can be calculated as follows:
Estimate using the Infinite Alleles
method and the 0.002 average are bulleted below. This estimate was
obtained from this site
Probability distribution of time to MRCA: Y
Chromosome markers that explains in
further details how this information was calculated for test results with
2 single step mutation.
They have a 50% chance of having a
common ancestor within 61 generations.
They have a 90% chance of having a
common ancestor within 122 generations.
They have a 95% chance of having a
common ancestor within 144 generations.
25 Marker Test - Time to Closest Ancestor
Test results having an
exact match on all 25 markers, time to their
closest ancestor, can be calculated as follows:
Estimates using the Infinite Alleles
method and the standard mutation rate of 0.002 are bulleted below. This estimate was
obtained from this site
Probability distribution of time to MRCA: Y
Chromosome markers that explains in
further details how this information was calculated for test results
reflecting a 12 marker match.
They have a 50% chance of having a
common ancestor within 7 generations.
They have a 90% chance of having a
common ancestor within 23 generations.
They have a 95% chance of having a
common ancestor within 30 generations.
Estimates using the Infinite Alleles
method and a high mutation rate of 0.004 are bulleted below.
They have a 50% chance of having a
common ancestor within 4 generations.
They have a 90% chance of having a
common ancestor within 12 generations.
They have a 95% chance of having a
common ancestor within 15 generations.
