Announcement

Collapse
No announcement yet.

How close this match to me?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • How close this match to me?

    Dear All,
    In my Family Finder matches, I have found a match that is shared with me ( Shared CM = 58 , Longest Block = 21) and Relationship Range ( 2nd - 4th cousin).

    Now, I need to know that, what is the exact relationship with this match? Is he a distant or a close match to me? What generation does he share with me? Can any body calculate the distance and the relationship ?

    I am looking forward to hear from you soon
    Thank You All

  • #2
    Try using this website - DNA Painter | Shared cM Project 4.0 tool v4 with relationship probabilities

    Comment


    • #3
      Originally posted by Jim Barrett View Post
      Thank you Jim, but this website only calculates the ( Shared CM) but it doesn't calculates the (Longest Block). I mean how the Longest Block will affect the relationship? Will it make the relationship closer to me?
      Last edited by NayefAlessa; 1 March 2021, 10:26 AM.

      Comment


      • #4
        The general opinion today is that the total shared cM is a much better predictor than the size of the longest segment, for estimating the degree of relationship.

        Comment


        • #5
          Originally posted by John McCoy View Post
          The general opinion today is that the total shared cM is a much better predictor than the size of the longest segment, for estimating the degree of relationship.
          Good, I have open the website that you write it to me, and it shows me that im a 3rd cousin once removed with my match ( Shared Cm = 58).

          Comment


          • #6
            Originally posted by John McCoy View Post
            The general opinion today is that the total shared cM is a much better predictor than the size of the longest segment, for estimating the degree of relationship.
            But there is something strange, that i had test the Family Finder to my father and my uncle from mother side. But this match that im talking about it doesn't appear to my father kit nor my uncle kit, but it only match me.

            How could a 3rd cousin match that match my kit but doesnt match my paternal and maternal side? is there an error or something?

            Comment


            • #7
              One thing to consider is that as the degree of relationship becomes more distant, the chance of not matching at all increases. If the relationship is, for example, a 3rd cousin once removed, there is an increased chance of less DNA shared than with a 3rd cousin. According to the charts at the ISOGG page for Cousin Statistics, a 3rd cousin will share DNA with you greater than 90% of the time at FTDNA, or about a 10% chance they won't share any DNA with you (or your maternal uncle). But, if the match is a child of a 3rd cousin (3rd cousin once removed), or a 4th cousin, then the average percentage shared decreases, so that there may be more than a 50% chance you will not share any DNA, according to FTDNA statistics. These estimates vary from one company to another.

              Your maternal uncle may fall into the "not sharing" range with this match, so this person won't show up as a match to him. But your mother may have shared more DNA with this match than your uncle, in a segment which she passed down to you. If you have any siblings, have they done the Family Finder test? It is possible they may show the same match, if the sibling has the same mother. Since siblings do not always inherit the same segments of DNA from a parent, it is also possible that they won't match this person.

              Another factor is that many of the possible relationships shown for your 58 cM match using the Shared cM Project Tool v. 4 are either probable half cousins, some distance of cousin removed, or both. A half cousin may be related via a child of a second husband or wife of an ancestor, so check those lines back several generations to see if the connection could be through such a couple.

              Comment


              • #8
                I should also add that currently FTDNA adds all segments to the total segment count for a match, even those segments as small as 1 cM. Many genetic genealogists recommend a minimum segment size of 7 cM or greater, in order to count as being Identical by Descent, or IBD*. Segments that are smaller can be Identical by State, or IBS**. (those two links are to very detailed descriptions in the ISOGG Wiki; see below for more brief definitions)

                To get a more realistic total for segments which are IBD, you should do the following:
                • Select your 58 cM match from your Family Finder match list, by checking the box to the left of his or her name in the list.
                • Choose the "Chromosome Browser" button at the top left of your Family Finder Matches page (the Chromosome Browser page may open in a new tab).
                • You will then see a representation of the segments you share with this match. Select "Detailed Segment Data" to see the data for each segment shared.
                • From the "Detailed Segment Data," note ONLY the segments which are 7 cM or over ("Centimorgans(cM)" column), and add them up. This will be the total you should use with the Shared cM Project 4.0 v. 4 tool.
                The total you get after the above process may only reduce the 58 cM by a small amount, or it could reduce by enough to make a difference in the relationship possibilities at the Shared cM Project tool. I have read that FTDNA is working on a new matching algorithm for the Chromosome Browser, so these small IBS segments will not be added to the total. But until the algorithm has been updated, use the above method to get a better IBD total.
                * and ** are defined in the FTDNA Learning Center Glossary (under the letter "I") as:
                * For Identical by Descent:
                "This means the DNA matches because it comes from a common ancestor. IBD can refer to a single mutation or to a segment of DNA. If a mutation or segment of DNA is IBD among a group of people, it comes from a common ancestor.The Family Finder relationship predictions require a minimum number of results in a row to be identical in order to identify that the segment is likely to be IBD."
                ** For Identical by State:
                "IBS stands for identical by state, meaning the DNA matches by coincidence. When two individuals share numerous individual results without being related, those results are IBS."
                Last edited by KATM; 1 March 2021, 03:14 PM.

                Comment


                • #9
                  Originally posted by KATM View Post
                  I should also add that currently FTDNA adds all segments to the total segment count for a match, even those segments as small as 1 cM. Many genetic genealogists recommend a minimum segment size of 7 cM or greater, in order to count as being Identical by Descent, or IBD*. Segments that are smaller can be Identical by State, or IBS**. (those two links are to very detailed descriptions in the ISOGG Wiki; see below for more brief definitions)

                  To get a more realistic total for segments which are IBD, you should do the following:
                  • Select your 58 cM match from your Family Finder match list, by checking the box to the left of his or her name in the list.
                  • Choose the "Chromosome Browser" button at the top left of your Family Finder Matches page (the Chromosome Browser page may open in a new tab).
                  • You will then see a representation of the segments you share with this match. Select "Detailed Segment Data" to see the data for each segment shared.
                  • From the "Detailed Segment Data," note ONLY the segments which are 7 cM or over ("Centimorgans(cM)" column), and add them up. This will be the total you should use with the Shared cM Project 4.0 v. 4 tool.
                  The total you get after the above process may only reduce the 58 cM by a small amount, or it could reduce by enough to make a difference in the relationship possibilities at the Shared cM Project tool. I have read that FTDNA is working on a new matching algorithm for the Chromosome Browser, so these small IBS segments will not be added to the total. But until the algorithm has been updated, use the above method to get a better IBD total.
                  * and ** are defined in the FTDNA Learning Center Glossary (under the letter "I") as:
                  * For Identical by Descent:
                  ** For Identical by State:
                  Thank you, after i do the method that you mention it to me, it gives me that the match share with me ( 29 CM). Maybe 4th cousin

                  Comment


                  • #10
                    Does your match have a tree? If so, try to view it in both the pedigree and family views. With the family view, you may be able to see if there are any ancestors of your match who had more than one spouse, and if they had other children with those spouses. This is in case your match is descended from a half sibling, so would be a half cousin (at some degree removed) to you.

                    Otherwise, look for familiar surnames. Check the match's profile to see if any locations are listed that might be in common with your ancestors. If you find anything in common, contact the match, but start simply and mention what you think may be the connection. Don't get too detailed right away.

                    Comment


                    • #11
                      Identifying the common ancestor is often very difficult. For a 29 cM match, about all you can say with any certainty, is that the relationship is in the range of third cousin or even more remote. Finding additional kits that triangulate on this segment may help, but much depends on someone posting a pedigree that is reasonably complete to about 4-5 generations back and that happens to include someone you can identify from your own pedigree. In spite of that, don't give up! Patience and persistence are the key to success in genealogy.

                      Comment

                      Working...
                      X