Ancestry DNA question

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Just a simple question about "hidden" matches so I'm sure I've understood it properly.

My closest match is the son of my maternal cousin at 568 cM - let's call him LC.

If I click on his profile and look at shared matches, will it show only people who share at least 20cM with both of us?

And if click on the profiles of other people and look at that shared match list, will it only show LC if he shared at least 20cM with them?

If someone shared 19cM with LM and that connection showed up on their shared match lists, it would be so much easier to determine whether people are maternal relatives of mine or not!

 

[scotmum]

Would LC consider inviting you as a 'viewer' of their matches? It can prove very useful in situations such as this.

https://support.ancestry.co.uk/s/article/Sharing-AncestryDNA-Results

[melba_schmelba]

Just a simple question about "hidden" matches so I'm sure I've understood it properly.

My closest match is the son of my maternal cousin at 568 cM - let's call him LC.

If I click on his profile and look at shared matches, will it show only people who share at least 20cM with both of us?

No. It will show people who share ANY DNA with LC (down to whatever minimum Ancestry uses, which no one is quite sure of since 9cM of two segments are quite regularly found) but only those who ALSO share a minimum of 20cM with YOU. Apologies for the capitals, but I feel sometimes I need to remind myself of this rule since it baffled me for yonks .

And if click on the profiles of other people and look at that shared match list, will it only show LC if he shared at least 20cM with them?

No the amounts shown in the shared match lists are all about YOU and how many cM that person connects to you.

If someone shared 19cM with LM and that connection showed up on their shared match lists, it would be so much easier to determine whether people are maternal relatives of mine or not!

 

Who's LM   . If you go through your own matches below 20cM, you will see they still have shared matches with you - you'll even find some down to 9cM though it becomes progressively less I have found. Shared matches will still appear if they match you at 20cM or above, regardless of how much they match that other person.

[decor]

Just a simple question about "hidden" matches so I'm sure I've understood it properly.

My closest match is the son of my maternal cousin at 568 cM - let's call him LC.

If I click on his profile and look at shared matches, will it show only people who share at least 20cM with both of us?

No. It will show people who share ANY DNA with LC (down to whatever minimum Ancestry uses, which no one is quite sure of since 9cM of two segments are quite regularly found) but only those who ALSO share a minimum of 20cM with YOU. Apologies for the capitals, but I feel sometimes I need to remind myself of this rule since it baffled me for yonks .

And if click on the profiles of other people and look at that shared match list, will it only show LC if he shared at least 20cM with them?

No the amounts shown in the shared match lists are all about YOU and how many cM that person connects to you.

If someone shared 19cM with LM and that connection showed up on their shared match lists, it would be so much easier to determine whether people are maternal relatives of mine or not!

 

Who's LM   . If you go through your own matches below 20cM, you will see they still have shared matches with you - you'll even find some down to 9cM though it becomes progressively less I have found. Shared matches will still appear if they match you at 20cM or above, regardless of how much they match that other person.

Thank you, Melba.
I think I need to print this out so I can read it over and over until I know it off by heart 

The thing that confuses me is:
I have a match with LC (son of maternal cousin) of 568cM as well as a match with PE (son of paternal cousin) of 520cM. This is very useful for knowing whether my matches are paternal or maternal.
HOWEVER I have matches as high as 42cM (for example, AR) where the shared matches don't include either LC or PE. Going by what you explained to me, this means that neither LC or PE have AR as a DNA match, which surprises me somewhat. I realise it's technically possible, but just a bit surprising.

[melba_schmelba]

Thank you, Melba.
I think I need to print this out so I can read it over and over until I know it off by heart 

The thing that confuses me is:
I have a match with LC (son of maternal cousin) of 568cM as well as a match with PE (son of paternal cousin) of 520cM. This is very useful for knowing whether my matches are paternal or maternal.
HOWEVER I have matches as high as 42cM (for example, AR) where the shared matches don't include either LC or PE. Going by what you explained to me, this means that neither LC or PE have AR as a DNA match, which surprises me somewhat. I realise it's technically possible, but just a bit surprising.

It is not unusual that you will have a 40 something cM match that won't have shared matches, even if you have some fairly close relatives on your DNA. Siblings share 50% on average, nephews/nieces/aunts/uncles or grandparents/grandchildren share 25% on average, but 1st cousins only share 12.5%, the same as a great grandparent and their great grandchild. So a 1st cousin once removed will only share the same amount as a great great grandparent and their great great grandchild i.e. 6.25% on average. So that leaves 93.75% of your DNA that you don't share with LC or PE, plenty of DNA to match others which they will not match, even if they share a close common genealogical ancestor with that person you are looking at.

[decor]

Thank you, Melba.
I think I need to print this out so I can read it over and over until I know it off by heart 

The thing that confuses me is:
I have a match with LC (son of maternal cousin) of 568cM as well as a match with PE (son of paternal cousin) of 520cM. This is very useful for knowing whether my matches are paternal or maternal.
HOWEVER I have matches as high as 42cM (for example, AR) where the shared matches don't include either LC or PE. Going by what you explained to me, this means that neither LC or PE have AR as a DNA match, which surprises me somewhat. I realise it's technically possible, but just a bit surprising.

It is not unusual that you will have a 40 something cM match that won't have shared matches, even if you have some fairly close relatives on your DNA. Siblings share 50% on average, nephews/nieces/aunts/uncles or grandparents/grandchildren share 25% on average, but 1st cousins only share 12.5%, the same as a great grandparent and their great grandchild. So a 1st cousin once removed will only share the same amount as a great great grandparent and their great great grandchild i.e. 6.25% on average. So that leaves 93.75% of your DNA that you don't share with LC or PE, plenty of DNA to match others which they will not match, even if they share a close common genealogical ancestor with that person you are looking at.

Quite right, Melba 
Maybe in the future, more of my close maternal relative will do a DNA test. There are people "higher" up the tree than LC who would do a better job of "sifting out" the matches from my maternal side, but none interested so far in doing the DNA test.

Thanks for your clear explanations
Andy 

[melba_schmelba]

Quite right, Melba 
Maybe in the future, more of my close maternal relative will do a DNA test. There are people "higher" up the tree than LC who would do a better job of "sifting out" the matches from my maternal side, but none interested so far in doing the DNA test.

Thanks for your clear explanations
Andy 

In my experience, just asking a person if they want to do a DNA test may not be successful, as they may only have heard negative things from various reports in the media i.e. FamilyTreeDNA being hacked, dubious medical results, dubious ancestry ethnicity reports, people finding out their parent was not who they thought etc. So when asking I would always state why you would like them to do it, and in what way it can be useful to you and them if they are interested in their family history.

[Flemming]

Just a simple question about "hidden" matches so I'm sure I've understood it properly.

My closest match is the son of my maternal cousin at 568 cM - let's call him LC.

If I click on his profile and look at shared matches, will it show only people who share at least 20cM with both of us?

No. It will show people who share ANY DNA with LC (down to whatever minimum Ancestry uses, which no one is quite sure of since 9cM of two segments are quite regularly found) but only those who ALSO share a minimum of 20cM with YOU. Apologies for the capitals, but I feel sometimes I need to remind myself of this rule since it baffled me for yonks .

Can I just check this? I have matches who are >20cM (let's call them 'A') and their profile shows no shared matches with me.

I also have matches <20cM (let's call them 'B') and their profile shows that 'A' is a shared match between us.

So... I can see 'A' on 'B's profile, but I can't see 'B' on 'A's profile. When I've checked this, 'A' and 'B' share >20cM.

Is this what you're saying in the above post?

[melba_schmelba]

Just a simple question about "hidden" matches so I'm sure I've understood it properly.

My closest match is the son of my maternal cousin at 568 cM - let's call him LC.

If I click on his profile and look at shared matches, will it show only people who share at least 20cM with both of us?

No. It will show people who share ANY DNA with LC (down to whatever minimum Ancestry uses, which no one is quite sure of since 9cM of two segments are quite regularly found) but only those who ALSO share a minimum of 20cM with YOU. Apologies for the capitals, but I feel sometimes I need to remind myself of this rule since it baffled me for yonks .

Can I just check this? I have matches who are >20cM (let's call them 'A') and their profile shows no shared matches with me.

I also have matches <20cM (let's call them 'B') and their profile shows that 'A' is a shared match between us.

So... I can see 'A' on 'B's profile, but I can't see 'B' on 'A's profile. When I've checked this, 'A' and 'B' share >20cM.

Is this what you're saying in the above post?

Shared matches will only show up in Ancestry shared match lists, if those matches match you at 20cM or more. So when you look at the shared matches for A, as B shares less than 20cM with you, it will not show on the shared match list, even though it is really a shared match between you and A. It doesn't make any difference as to how much A shared with B, you can't find that out unless you ask the persons, or ask them to share their DNA with you

https://support.ancestry.co.uk/s/article/Sharing-AncestryDNA-Results