This Group is also known as the Irish Sea Cluster

This group of families has two members who can trace their ancestry back to the original Scottish loyalists settling in Ontario, Canada after the revolutionary war. There is no information on where they may have come from in Scotland yet, although some clues hint at the Glen Moriston area.

This group also links closely with the Beatty-Byrnes Cluster, also known as the BBC or Irish Sea Cluster.

The Byrnes family is  linked to the Laigin chieftains who governed in Leinster Ireland and are thought to be descendants of an early Celtic people. Perhaps the best known of the Lagin or Leinster chieftains were the MacMurroughs. Dermot MacMurrough was the king of Leinster who c. 1170 invited the Normans into Ireland. This line later splintered into the Kavanaghs and Kinsellas. Despite the encroachment of the Normans on their territories in Leinster these two families maintained their prominence in the south of Ireland until the 1600s. The O’Byrnes were also a powerful Leinster sept

The Beattys were border raiders on the west coast of the Scottish lowlands. Other Scottish names linked to this DNA grouping are: McCloughan, McLaughlin, Carmack, McInvale, Ferguson, McDonald, McConnell, and Davidson.

For more information on how DNA is being used to unravel this historical puzzle, see John McLaughlin’s post.

Kits in this group are 63180, 73524, 123741, 138783, and N89565.

Reading the Genetic Distance Chart

If you look at kit 73524 in the top line and kit 138783 in the left column, the square where they intersect is a greeen 1.

FIRST look for the color in the squares. Green means a definite relationship, Yellow is a probable relationship, and Red is a possible relationship. In this case, there is definitely a relationship between kit 73524 and 138783.

THEN look at the number in the square. This is the numerical difference between two sets of markers and is useful for calculating the number of generations back the two families are likely to have shared a common ancestor. In this case, the genetic distance is 1.

The white boxes reflect the number of markers tested in that particular kit. Look where 63180 across the top intersects with the line from 63180 in the left column–there is white square with “67″ in it.

Modal is basically the average marker values for all the people in this group and is best used for statistical analyses of large groups.

Once you find relationships you are interested in, scroll down below to the Time to Most Recent Common Ancestor Chart

Genetic Distance
ID	m o d a l	6 3 1 8 0	7 3 5 2 4	1 2 3 7 4 1	1 3 8 7 8 3
modal	37	0	2	0	1
63180	0	12	1	0	1
73524	2	1	37	2	1
123741	0	0	2	37	1
138783	1	1	1	1	25

The same principles apply to reading this chart. TMRCA requires an estimate of the number of years between generations. This example uses 30 years.

Time to Most Recent Common Ancestor (Years)
ID	m o d a l	6 3 1 8 0	7 3 5 2 4	1 2 3 7 4 1	1 3 8 7 8 3
modal	37	450	360	90	450
63180	450	12	1110	450	1110
73524	360	1110	37	360	450
123741	90	450	360	37	450
138783	450	1110	450	450	25