Shared cM amounts Causing Confusion

[KiwiAuckland]

I've got a sneaking suspicion that I'm asking a really stupid question but I've scoured the website/forums looking for the answer, so exposing my ignorance to all of you is a last resort

On the page displaying the Family Finder matches, my husband's highest match shares 73.74cM. Now when I check that same match on chromosome browser, it displays two matching orange segments that only total 39.57cM. So where is the missing 34.17cM that my husband and this person are said to share?

I've tried other matches and get similar discrepancies. If anyone can provide a simple explanation, it would be much appreciated.

Also, while I've got your attention we are waiting for FF results to come through for a person who's agreed to test for us in order to solve a 120 yr old family (paternity) mystery. Now we're hoping this person and my husband are third cousins, once removed. But from what I've read on here, there's a chance their relationship won't be close enough to show them as matches on FF? Is this correct?

[travers]

The 73.74 total they give you includes segments under 5cM wheras the default setting on the chromosome browser only shows segments at 5cM or above, you can view the smaller segments if you wish by selecting them in the drop-down box. As far as the 3rd cousin once removed, yes there is a chance they won't match. You have a 90% chance of matching a 3rd cousin and around a 50% chance of matching a 4th cousin so a 3rd cousin once removed is in between about a 70% chance.

[Yaffa]

Have same problem. Match shows as 70cm and chrome browser states 7.73 cm.

My match is from Sweden and no way could they match me on 70 cm. We have no one from Sweden in our family.

[Yaffa]

Forgot to add this person was never in my matches before and they tested in June. This person is listed as distant remote and they should be if they only match me possibly on 7cm, why it comes up as a closer match stating 70 cm???

[KiwiAuckland]

you can view the smaller segments if you wish by selecting them in the drop-down box. .

Many thanks - that makes sense, especially now that I notice on the side they have 18 matching segments and I had the settings only displaying the two largest. I thought that smaller segments were not important and more likely to be "noise" but given that the largest shared segment is 32.49cM then I suppose it's safe to assume they are actually related. Albeit distantly.

[MerryB]

Forgot to add this person was never in my matches before and they tested in June. This person is listed as distant remote and they should be if they only match me possibly on 7cm, why it comes up as a closer match stating 70 cm???

One possibility-- they match you distantly through more than one line. Otherwise, what does it say for tiny sized matching segments?

[mkdexter]

When FTDNA changed their user interface they removed the longest block reading. Maybe this is what is causing some confusion..... If so.

To see longest block, in addition to sum cM, choose the "SHOW FULL VIEW" option at the top left of the Matches page.

[Yaffa]

Matt, I sent you a PM but Ill post here what is going on just in case others are having same issue


I have to call FTDNA here is the problem when I use all matches, and cm amount this Sweden match shows up as 70cm and states longest bock 7.73 but when I get in chrome browser the cm is 7.73 not the longest block. If I just search on all matches this Sweden match is on my last page of matches but still states 70 cm even though he is listed as distant match. There is a glitch between longest block and cm amount.

[travers]

I have to call FTDNA here is the problem when I use all matches, and cm amount this Sweden match shows up as 70cm and states longest bock 7.73 but when I get in chrome browser the cm is 7.73 not the longest block. If I just search on all matches this Sweden match is on my last page of matches but still states 70 cm even though he is listed as distant match. There is a glitch between longest block and cm amount.

I assume you have done this but bring up your Sweden match in the chromosome browser and click near the top where it says "View this data in a table". Then add up all values in the "CentiMorgans (cM)" column, does it add up to 70 cM? If all it adds up to is 7.73 it is definitely a glitch of some kind as you need to share about 20 cM total to even trigger a match.

[Yaffa]

I assume you have done this but bring up your Sweden match in the chromosome browser and click near the top where it says "View this data in a table". Then add up all values in the "CentiMorgans (cM)" column, does it add up to 70 cM? If all it adds up to is 7.73 it is definitely a glitch of some kind as you need to share about 20 cM total to even trigger a match.

It adds up to 7.73 and is most certainly a glitch. There is no way we could match anyone from Sweden at 70cm anyway.

[mkdexter]

Out of curiousity, what are apt he longest block amd sum on the matches page?

[Yaffa]

Matt, I called FTDNA and they said that if I lower the match that I do in fact match this person on 70 cm worth of small segments but the longest block is 7.73. They agree this is a very strange match I have. Even though population finder has nothing to do with cousin matches I did mention that this could be mistaken for AI matches like people who are AI being given Finn/Russian on population finder. Its just a theory but I would have to match up all these little segments to see how many other colonial US this person might over lap on. This is all I can think of on this strange match but it is one of my most distant matches. I do not have any record of Nordic being in my family or Dutch for that matter so I cant explain this Sweden match.

[mkdexter]

Thanks Yaffa for posting your update on this one...

[Yaffa]

Your welcome Matt. Just triangulated this match and in general we share very few matches who seem to be colonial and one other who also seems to be Swede and very distant. I need to go play in chrome browser but this is still strange