Kitty Cooper has launched her Chromosome Mapper tool page. This useful tool allows you to color code DNA segments you share with cousins once you have determined your common ancestor. This post covers the basics of using it.

It is web based, so to use it you need only visit her website,

Chromosome Mapper

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The program takes data directly downloaded from Family Tree DNA and 23andMe. You can also use pull files from the DNAGedcom site. It is not fussy about the order of columns. However, you do need to get the column names right: side, Chr, Start point, End point, cMs, and MRCA. For the first example, I return to my father’s cousins identified as having Quaker (Religious Society of Friends) ancestry yesterday. This map is done from the perspective of my father. His Quaker ancestry is from his mother’s father, James Arnold Elliott. Thus, I designate the side as Maternal. I do not know the exact MRCA (Most Recent Common Ancestor), so I simply put A Quaker.

Chromosome Information for Chromosome Mapper

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Once the information has been formated, be sure to save it as a CSV file.

Save Data as a CSV file

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Now, return to the Chromosome Mapper website. Click on the Choose File button to load the CSV file you created.

Click Choose File to load your CSV file

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Click the Make the Chromosome Map button to generate your map.

Make the Chromosome Map

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The product is a simple Chromosome map.

This is the output of the Chromosome Mapper program

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Only one MRCA was designated, so the map only shows one color. My next post will show how to create a more complex map using Family Tree DNA’s In Common With and Not In Common With triangulation filters.