Source: http://www.differencebetween.info/difference-between-ethnicity-and-culture |
But how do we determine the "ETHNICITY" of these shared DNA segments? In this deep dive my objective is to discuss an underutilized (it's not new) method -- I'll coin this process Ethnicity Chromosome Mapping* (ECM) -- that can be used in conjunction with chromosome browsing, mapping and triangulation to determine the ethnicity of shared DNA segments as outlined here:
SECTION I. Instructions (4 steps) for using ECM to find "Ethnicity" of shared DNA segments
-- STEP 1. Identify location and size of potential shared DNA segments using chromosome browsing and mapping tools (CBaMt)
-- STEP 2. Identify potential "ethnicity" of shared DNA segments using CBaMt
-- STEP 3. Find “START POINTS” AND “END POINTS” of shared DNA segments using CBaMt
-- STEP 4. Confirm “ethnicity” of shared DNA segments using Gedmatch's "Paint the Difference Between 2 Kits, 1 chromosome" tool
SECTION II. ECM Pitfalls and Technical Notes
-- (a) What happens when the "ethnicity" of shared IBD DNA segment does NOT match?
-- (b) Technical notes about Chromosome Paintings
-- (c) Technical notes about Gedmatch's "Paint the Differences..." tool
-- (b) Technical notes about Chromosome Paintings
-- (c) Technical notes about Gedmatch's "Paint the Differences..." tool
WHAT YOU WILL NEED:
Your results and access to 23andMe, FamilyTreeDNA, AncestryDNA, and third-party site Gedmatch.com. For optimal results, ECM works best under these conditions:
- shared DNA segments (aka half-identical regions or HIRs; see also fully identical regions) between two persons who appear to share a genetic relationship must be Identical By Descent or IBD (indicates a real genetic relationship) and NOT Identical By State or IBS (indicates shared ancestral population). To be considered IBD, the standard threshold for HIRs is generally* 7cM/700 SNPs or higher (with triangulation, 5cM/700 SNPs or higher) [*see Blaine Bettinger's blog here and here; Roberta Estes blog here & Kitty Cooper's blog here]; AND
- shared ethnic component(s) between genetic matches is easily distinguishable from other ethnic components in same general location on the chromosome painting; AND
- you've tested several known close relatives, AND
- all tested parties have uploaded their raw DNA data to Gedmatch.com and have successfully registered kit numbers.
SECTION I.
Instructions (4 steps) for using ECM to find "ETHNICITY" of shared DNA Segments
Instructions (4 steps) for using ECM to find "ETHNICITY" of shared DNA Segments
- 23andMe's Family Inheritance: Advanced (FIA) & DNA Relatives Triangulation tool (note: Countries of Ancestry tool is now defunct);
- FTNDA's Family Finder - Chromosome Browser;
- Gedmatch.com One to One tool (for AncestryDNA, 23andMe, FTDNA)