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The GEDmatch.com Chromosome Segment Matching report has the following legend:

One of my reports has the following triangulation match:

The purple segment (< 5 cm) is 102912701 - 111046063 (4.189 cM) and the green segment (10-20 cM) is 149430788 - 154663050 (11.939 cM).

Since the green segment is almost 3 times as many cM, why does the visual show the purple segment being almost twice as long? Is the match somehow spread out with bits of non-matching portions mixed in, thus getting elongated?

Also, what does the `F2`

type mean (not show in image)? I'm getting `F2`

on each matching person's table entry above the graphic such as the shown one above.

Does such a matching segment mean the two kits are identical in the regions shown?

I'm asking if the kits are identical in the colored matching segments? – WilliamKF – 2016-09-28T17:58:33.970

Each row in the display shows the segments of one person. That is represented by the "1" at the left and the right of your graphic and by the "Match ID" in my graphic. So yes, the segments in that row, the purple and green segments, both use the same kit, the kit of person with ID 1. – lkessler – 2016-09-28T19:26:54.837

The legend offers >100 cM, so how could the change of crossing over be greater than 100%? – WilliamKF – 2016-09-30T01:05:32.733

1To be more precise, cM is actually the expected number of crossovers on the segment in one generation multiplied by 100. So for example, a 120 cM segment might get 0, 1, 2, or even 3 or more crossovers, but should average to about 1.2 crossovers. The DNA totals about 3800 cM, and averages about 38 crossovers per generation over all the chromosomes. For small values of cM, e.g. 11.9 cM, the chance 11.9% of a crossover on that segment is approximately equal to 0.119 the expected number of crossovers. – lkessler – 2016-09-30T13:07:25.417