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From listmasteranimalgenome.org  Wed Feb 20 08:43:36 2019
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From: Yuri Tani Utsunomiya <ytutsunomiyagmail.com>
Subject: Re: software for exact p-values for association
        analysis on single step gblup
Postmaster: submission approved by list moderator
To: Members of AnGenMap <angenmapanimalgenome.org>
Date: Wed, 20 Feb 2019 08:43:36 -0600
Dear Andres,

I am a little bit confused with the proposed test.

As far as my limited knowledge goes, classic t-distributed statistics are
ratios between estimates of parameters of interest and their respective
standard errors. In the manuscript, the denominator of the ratio seems to
be the square root of the variance due to the tested marker instead (i.e.,
marker standard deviation), which is not the same as the standard error of
the estimate. The latest information I had was that the standard errors of
marker effects in GBLUP and ssGBLUP do not have a simple or even known
expression for fast computation, and therefore they should be approximated
with resampling procedures such as bootstraping, subsampling or
jackknifing. Please do not take this observation as a critic, but rather as
a question that - I believe - many of us users of blupf90 have. Last but
not least, I apologize if my read of the proposal is incorrect.

Cheers,
Yuri Utsunomiya

On Wed, Feb 20, 2019 at 10:36 AM Andres Legarra-Albizu <andres.legarrainra.fr> wrote:

> Dear all,
>
> thanks to collaborative work and extensive programming, I, on behalf of all
> the blupf90 team, am happy to announce that the blupf90 suite now computes
> exact p-values for gwas analysis - same as “one at a time” classical
> gwas by regression. The authoritative reference is this biorxiv deposit:
>
> MS ID#: BIORXIV/2019/555243
>
> MS TITLE: Exact p-values for large-scale single step genome-wide
> association, with an application for birth weight in American Angus
>
> These requires the use of OPTION snp_p_value in programs blupf90 (or
> blupf90test) and postGSf90. More details in the corresponding sections in
> the wiki:
>
> http://nce.ads.uga.edu/...application_programs
>
> regards, Andres
>
> --
> Andres Legarra
> +33 561285182
> INRA, UMR1388 GenPhySE
> CS 52627
> 31326 Castanet Tolosan, France
> http://genoweb.toulouse.inra.fr/~alegarra

--
*Yuri T. Utsunomiya*
DVM/MSc/PhD
Sao Paulo State University (UNESP - Brazil)
School of Veterinary Medicine - Department of Support, Production and
Animal Health (Araçatuba/SP)
International Atomic Energy Agency (IAEA) Collaborating Centre on Animal
Genomics and Bioinformatics
Laboratory of Animal Biochemistry and Molecular Biology


 

 

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