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How do I use the Chromosome Browser — One-to-many?

The Chromosome Browser — One-to-many allows you to compare DNA segments between you (or any of the people whose DNA kits you manage) and up to seven DNA Matches. By studying those shared segments and testing the DNA of additional relatives, it is possible to determine who the segments originated from and in turn, determine the relationship between the people who have taken the DNA test.

To navigate to the One-to-Many Chromosome Browser, please do as follow:

1. Hover over the DNA tab and select “Chromosome Browser”:

2. The One-to-Many Chromosome Browser page will open. Select the main person you want to compare with his or her DNA Matches by clicking on the arrow next to “Compare”. 

You can choose yourself, or any of the people whose DNA kits you manage. If you have only one DNA kit, of yourself, then this part is pre-selected.

3. Now, build the comparison set. These are the DNA Matches you’d like to compare the main person to. Select at least one DNA Match, and at most up to seven, from the list of available DNA Matches displayed as detailed cards at the bottom of the page. 

Note that the available DNA Matches are sorted by shared DNA, meaning that more closely related people will be listed first. 

Simply click on a DNA Match to select it:

Each DNA Match you select will appear on the top row: 

After you select a DNA Match to compare, his or her card at the bottom of the page will appear dimmed to help you keep track of which DNA Matches you’ve already selected.

If you change your mind after selecting a DNA Match, hover over the card in the top row and click on it to remove it.

If you want to undo the entire selection, click “Clear” on the right-hand side.

You can use the search facility to locate any specific match you’re looking for, if they are further down in the list and you don’t want to scroll manually to look for them. 

You can also move to the next page from the bottom of the current page:

Tip! Select DNA Matches that you think might be related to each other, or are possibly from the same branch. For example, if you were looking at a DNA match between you and a person named John Smith, and the DNA Match Review page showed you that you and John both match another person named Samantha Miller, it would make sense to explore you, John and Samantha together in the One-to-Many Chromosome Browser, and check for the existence of triangulated segments.

Once you have selected all of the DNA Matches you want to include in the comparison set, click the “Compare” button on the right:

When you initiate a comparison, the Chromosome Browser springs into action. 

The top of the page now displays one or more Match Cards with a colored bar on top, representing your match with each specific DNA Match you selected. 

You can change the selection at any time if you click “Add or remove DNA Matches” on the right-hand side of the colored cards. This will get you back to the previous page. 

If you place your mouse in the corner of a Match Card, three dots will appear. Click on the three dots to find options to review or contact the DNA Match: 

Each Match Card reminds you of the DNA Match parameters between you and that person (shared DNA, number of shared segments, and the size of the largest segment). Read the following article for more detail: How does MyHeritage calculate the potential relationship in DNA Matches?

Below, for each one of the 22 chromosomes, the DNA segments that you share with each one of the selected DNA Matches will appear in the same color as on the Match Card. The color coding helps you keep track of the various matches. 

Gray segments are not shared with the DNA Match and the small crisscrossed sections represent segments that were not analyzed due to a lack of DNA markers (SNPs) in those regions.

DNA segments indicated by a frame are triangulated segments — segments shared by all of the selected DNA Matches between each other. These segments were likely passed down to all of them by one or more common ancestors. 
Triangulated segments are exactly what you hope to find as they are a strong indication that all the people currently displayed in the Chromosome Browser are indeed descendants of the same common ancestor or ancestors. You might even know who the common ancestors are if your family tree goes back far enough. But if they are not in your tree you will need to extend your tree with more generations by doing more research and learning new information from your DNA Matches who may have conducted some family history research on their side.
The regions of DNA where all colored bars appear, but no triangulated segment is indicated there, means you share DNA segments at the same genomic position with multiple DNA Matches, but they do not share that segment with each other.

For further reading about triangulation: 

What are triangulated segments in the Chromosome Browser — One-to-many?

What does it mean if there are no triangulated segments shared between DNA matches?

When you hover your mouse over any shared DNA segment in a desktop browser, whether triangulated or not, you can review the genomic position of the shared segment, the size of the segment, and the number of SNPs there.

  • Genomic position indicates the start and end location of the matching segment. Millions of base pairs make up each chromosome. Knowing the first and last base pair of the shared segment tells you exactly where the shared segment is located on the chromosome.
  • RSID (Reference SNP cluster ID) indicates the “name” of each SNP. For each shared DNA segment you can see the first and last SNPs (start rsID and end rsID) of the segment.The rsID is a number used by scientists to identify specific SNPs in the genome. 
  • Segment size indicates the length of the matching segment, measured in centiMorgans (cM). The longer the segment is, the higher the chances that you’re related and that the relationship is closer.
  • Number of SNPs (Single Nucleotide Polymorphisms) within the matching segment. The number of SNPs in a segment gives you a sense of how confident you can be in the match.

At the bottom of the One-to-Many Chromosome Browser, below the visual display of the chromosomes, you will find information on the shared DNA segments:

Click the small arrow on the left side to see the detailed information:

You can download the shared DNA information between all the DNA matches in an CSV file if you click on “Advanced options” on the right, then “Download shared DNA info”:

Further reading: Major Upgrade to the MyHeritage Chromosome Browser for Better Exploration of DNA Matches