Questions tagged [gwas]
The gwas tag has no usage guidance.
84
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Estimating computing resources needed for a GWAS?
One of my dissertation papers is going to involve a GWAS. I have never actually run a GWAS before, and do not know how to estimate the computing resources I need for it. I asked someone on my ...
3
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1
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120
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How to perform liftover from 38 to 37 in R?
I have some gwas summary statistics in GRCh38 that I want to lift to GRCh37. I am trying to liftover in R using this code:
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2
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3
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314
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How do I lift GWAS results to hg38?
There are some questions about lifting between reference builds, e.g. this one. But there doesn't appear to be a question about lifting a GWAS results file to a new reference build (except off-site). ...
1
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1
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286
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LD clump GRCh38 GWAS results
The vignette of R package ieugwasr describes a plink based wrapper function for LD clumping GWAS data using the 1000 genomes ...
2
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1
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630
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GWAS in python?
A question similar to this has also been asked on Biostars
I understand GWAS is done with R, but are any written in Python?
I'm used to python and java, acclimating to R will take a bit of time and my ...
3
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2
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99
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Summary statistics version problem
I am learning GWAS study and PRS for predicting disease. I was aligning my sequencing data with GRCH38 reference panel. However, in the PRS analysis step, I found that most of the summary statistics ...
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0
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43
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PLINK linear association testing command with an interaction and 2 covariates term
I am trying to write the right command for my association testing using PLINK 1.9 but I could not find a clear answer so far and not sure how to wrtie it correct.
I have genotype variants called and ...
1
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2
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70
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Why does my HWE QQ plot have extreme deviation and what does it mean?
This question was also asked on Reddit
I have recently completed my thesis and one of the comments was that I report on why this graph looks this way. I have tried to find a reason but the closest I ...
5
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What does PCA mean on GWAS
I understand what GWAS is and I'm able to perform certain tests with the p-values, etc. But what I am having a hard time wrapping my head around is what PCA on GWAS means.
So let's say I have 100,000 ...
2
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2
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74
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Loss of predictive power of polygenic risk score when dataset contains missing variants
I am trying to calculate polygenic risk scores (PRS) scores for a new dataset. This dataset does not have all the variants that the PRS score needs. The PRS score I am interested in has 40 variants, ...
4
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1
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177
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How is the odds ratio of disease risk conferred by a 1-standard deviation increase in PRS calculated?
One standard deviation from the mean is commonly used to calculate a polygenic risk score for GWAS, e.g. human genetic disease.
Why is this a common metric, for example why not 2-SD or 1.96 SD as in ...
2
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1
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97
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How are the "effect_allele" and "other_allele" bases chosen in a PGS file from the PGS Catalog?
How are the "effect_allele" and "other_allele" bases chosen in a PGS file from the PGS Catalog?
For example, for PGS002723 (https://www.pgscatalog.org/score/PGS002723/), if I set ...
1
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1
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145
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Pandas automatically rounds GWAS P-value
I am working with a specific GWAS. If I were to run this on the command line
grep <rs_id_of_interest> GWAS.txt
I would see the GWAS p-value to be on the ...
2
votes
1
answer
522
views
Getting nearest gene from SNP data using SNP ID, CHR, and BP
I have data from a GWAS that provides me with the SNP, Chromosome, and base-pair. My data set has thousands of SNPs. What is the easiest way to find the nearest gene for each SNP using this ...
2
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2
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413
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How to z-transform Fst and -log(p) values for genome wide selection scan?
I saw in the literature a lot genome wide scans showing $F_{ST}$ values in a 'z-transformed' format which seems to be bounded between 0 to infinity.
Examples are found easily searching for 'genome-...