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View Full Version : What do fst distances show?

The Barnacle
12-12-2014, 06:11 PM
I'm new to this, what does fst distances show compared to oracle calculators etc? Thanks.

I'll be really grateful if someone could explain this to me because it's got me confused

dp
12-12-2014, 10:45 PM
WRT to Oracle admix calculators the lower the number the better. The tell you best fits.
dp :-)

AJL
12-12-2014, 10:57 PM
Fst is fixation index (http://http://www.nature.com/scitable/topicpage/using-snp-data-to-examine-human-phenotypic-706), a measure of distance to populations. As David said, the closer you are to zero, the less the distance.

The Barnacle
12-12-2014, 11:37 PM
Fst is fixation index (http://http://www.nature.com/scitable/topicpage/using-snp-data-to-examine-human-phenotypic-706), a measure of distance to populations. As David said, the closer you are to zero, the less the distance.

Great, however whats more accurate in terms of knowing who your closest population is to you? Fst distances or oracle? What do oracle show?

The Barnacle
12-12-2014, 11:38 PM
WRT to Oracle admix calculators the lower the number the better. The tell you best fits.
dp :-)
What do oracle shows?

AJL
12-13-2014, 12:15 AM
It's not an exact science and results will vary in accuracy for individuals but that does not always mean any one system is inherently better than another. The best bet is to look at results from multiple tests and see what signals are repeated.

Missouri1455
01-08-2017, 01:43 AM
at what number does the population distance lose it relevance?

Missouri1455
01-08-2017, 01:46 AM
If i have a repeated population at 30.00-25.00 distance does that make it very far away? and what percentage would that ethnicity amount up to?

dp
01-11-2017, 07:48 PM
25+ is not significant. That sounds like an Oracle1 value (and one for a very admixed individual)
Use Oracle4 to get a population mix with lower Fst.
d[ :-)

AJL
01-11-2017, 07:58 PM
To expand on dp's excellent answer, 1.00 would be a perfect match on single mode. Most people of a single ethnic origin, from a non-diverse population that is well represented in data sets, will end up below 4.00 on single mode. 25.00 is a horrible match, and while you might by chance have a percentage of your ancestry from that or a similar population, it's not a good representation of your ancestry overall.