M3 Flashcards
(27 cards)
What is a Chromosome Browser?
- A way to visually REPRESENT your 22 pairs of autosomes
- Can sometimes INCLUDE the X chromosome
- Can VISUALIZE shared segments of DNA w/a DNA match
- DNA matches who OVERLAP on the same segment on the same chromosome share a common ancestor
GEDmatch Chromosome Browser
Matches are NOT
sorted maternally or paternally, so ALL matches will appear to be overlapping on the same chromosome
Centromere
the region of a chromosome to which the microtubules of the spindle attach, via the kinetochore during cell division
What is a Matrix
- A way to visualize your DNA matches.
- See how your matches match (or don’t match) each other
Genetic Network
Group of matches
Shared matching
Groups of matches that MAY
share a common ancestor
GEdmatch Shared Matches Tool
People who match with both, or 1 of 2 kits
GEDmatch ICW Tool
In Common With
Clustering – The Leeds Method
- Manual way of clustering your matches
- List 2nd and 3rd cousins
- Assign color to first match
- Assign ALL SHARED matches the same color
- 1st DNA match NOT part of shared matches gets another color
- Continue until all shared matches have an assigned color
Clustering – Genetic Affairs by Evert-Jan Blom
Automated Clustering tool available on Genetic Affairs website
* When there is a large cluster of one color could indicate endogamous population
- Genetic Affairs is also available at GEDmatch
GEDmatch Triangulation
- One-To-Many matches
- Select Kits and click “Visualization Options”
- Select “Triangulation”
Triangulation
Just because there is OVERLAP
DOESN’T mean there is Triangulation
Triangulation Limitations
- Endogamy & Double Cousins
Endogamy
when you have multiple relationships with your matches, it can be difficult to know which ancestor to attribute the segment to
Double Cousins
when you share more than one common ancestor, it can be difficult to know which ancestor to attribute the segment to
Limitations
Tree Completeness
if your tree and the trees of your matches are not complete, you may attribute a segment to an ancestor when there may be another common ancestor you aren’t aware of
Limitations
Pile Ups AKA
Excess IBD or IBP
What is WATO?
WATO - What Are the Odds?
Understanding WATO Hypotheses
A higher score means a higher likelihood
that this hypothesis is correct. However, the most likely hypothesis is NOT always the correct one.
What is WATO?
Programmed by
Jonny Perl
What is WATO?
It is a way to identify an
unknown person, parent or ancestor
What is WATO?
You can ONLY use WATO if you know how
the member of a group of DNA matches are connected to each other
What is WATO?
It will tell you which hypotheses are
MOST LIKELY and which ones are NOT possible
Understanding WATO Hypotheses
A hypothesis is only as good as the hypothesis
it is being compared to. Missing hypotheses will cause inaccuracies.
