• Format data to mashr format
  • Run mashr
  • Get sharing
  • Estimate mixture proportion
  • Effect Size Comparison
    • Posterior Mean VS. Original Effect
    • Scaled by standard deviation: Posterior Mean VS. Original Effect

Last updated: 2020-01-04

Checks: 6 1

Knit directory: mash-single-cell-rnaseq/

This reproducible R Markdown analysis was created with workflowr (version 1.5.0). The Checks tab describes the reproducibility checks that were applied when the results were created. The Past versions tab lists the development history.


Great! Since the R Markdown file has been committed to the Git repository, you know the exact version of the code that produced these results.

Great job! The global environment was empty. Objects defined in the global environment can affect the analysis in your R Markdown file in unknown ways. For reproduciblity it’s best to always run the code in an empty environment.

The command set.seed(20191120) was run prior to running the code in the R Markdown file. Setting a seed ensures that any results that rely on randomness, e.g. subsampling or permutations, are reproducible.

Great job! Recording the operating system, R version, and package versions is critical for reproducibility.

Nice! There were no cached chunks for this analysis, so you can be confident that you successfully produced the results during this run.

Using absolute paths to the files within your workflowr project makes it difficult for you and others to run your code on a different machine. Change the absolute path(s) below to the suggested relative path(s) to make your code more reproducible.

absolute relative
/Users/nicholeyang/Desktop/Rotation/mash-single-cell-rnaseq/data/top_snps.RData data/top_snps.RData

Great! You are using Git for version control. Tracking code development and connecting the code version to the results is critical for reproducibility. The version displayed above was the version of the Git repository at the time these results were generated.

Note that you need to be careful to ensure that all relevant files for the analysis have been committed to Git prior to generating the results (you can use wflow_publish or wflow_git_commit). workflowr only checks the R Markdown file, but you know if there are other scripts or data files that it depends on. Below is the status of the Git repository when the results were generated:


Ignored files:
    Ignored:    .DS_Store
    Ignored:    .Rhistory
    Ignored:    .Rproj.user/
    Ignored:    analysis/.Rhistory

Untracked files:
    Untracked:  data/top_snps.RData
    Untracked:  top_snps.RData

Unstaged changes:
    Modified:   analysis/RNA_seq_process2.Rmd

Note that any generated files, e.g. HTML, png, CSS, etc., are not included in this status report because it is ok for generated content to have uncommitted changes.


These are the previous versions of the R Markdown and HTML files. If you’ve configured a remote Git repository (see ?wflow_git_remote), click on the hyperlinks in the table below to view them.

File Version Author Date Message
Rmd 892e43b Nicholeyang0215 2020-01-04 wflow_publish(“analysis/mashr_application.Rmd”)
html 59bbc5e Nicholeyang0215 2019-11-21 Build site.
Rmd 87a59f6 Nicholeyang0215 2019-11-21 wflow_publish(“analysis/mashr_application.Rmd”, verbose = TRUE)

Remarks:

  1. Used data from “Shared genetic effects on chromatin and gene expression indicate a role for enhancer priming in immune response” https://doi.org/10.1038/s41588-018-0046-7. eQTLs from 4 conditions downloaded from https://zenodo.org/record/1158560#.Xgjl5BdKhp8.

  2. For data preprocessing, we first filter with the criteria p-value <0.05. Then, take the top signals (the most significant SNP for each gene) in naive condition, and filter gene-SNP pairs in other conditions based on top signals in naive condition. The resulting “top_snps.RData” contains 15678 significant Gene-SNP pairs in 4 conditions.

  3. Mashr re-estimate the effect size of SNPs, incorporating information across conditions.

  4. Ways to access the fit. Log-likelihood and others?

library(ashr)
library(mashr)

Format data to mashr format

load("/Users/nicholeyang/Desktop/Rotation/mash-single-cell-rnaseq/data/top_snps.RData")

dt_beta <- top_snps[,c("beta_naive", "beta_IF", "beta_IFSL", "beta_SL")]
dt_pval <- top_snps[,c("p_nominal_naive", "p_nominal_IF", "p_nominal_IFSL", "p_nominal_SL")]

dt_beta = as.matrix(dt_beta)
dt_pval = as.matrix(dt_pval)

head(dt_beta)
  beta_naive    beta_IF  beta_IFSL    beta_SL
1 -0.3370090 -0.4037950 -0.0941426 -0.2029850
2 -0.0743763 -0.0419751 -0.0325720 -0.0214099
3 -0.0786190 -0.0507808 -0.0591935 -0.0275128
4  0.0826863 -0.0162367 -0.0407589  0.0786256
5 -0.4299870 -0.3545930 -0.2523280 -0.2987360
6 -0.3760470 -0.0694328  0.0700316 -0.0902658
head(dt_pval)
  p_nominal_naive p_nominal_IF p_nominal_IFSL p_nominal_SL
1      0.00061327   0.00140049      0.5007650    0.0545107
2      0.00121529   0.08250130      0.1340060    0.3738330
3      0.00117232   0.04579800      0.0610855    0.5071570
4      0.00256488   0.68539900      0.5733360    0.0466930
5      0.03554660   0.03811650      0.0227163    0.0728410
6      0.01376920   0.37466200      0.2537470    0.5845360
#str(dt_beta)
#str(dt_pval)

Run mashr

dt_mash = mash_set_data(dt_beta, Shat = NULL, pval = dt_pval)
head(dt_mash$Bhat)
  beta_naive    beta_IF  beta_IFSL    beta_SL
1 -0.3370090 -0.4037950 -0.0941426 -0.2029850
2 -0.0743763 -0.0419751 -0.0325720 -0.0214099
3 -0.0786190 -0.0507808 -0.0591935 -0.0275128
4  0.0826863 -0.0162367 -0.0407589  0.0786256
5 -0.4299870 -0.3545930 -0.2523280 -0.2987360
6 -0.3760470 -0.0694328  0.0700316 -0.0902658
head(dt_mash$Shat)
  beta_naive    beta_IF  beta_IFSL    beta_SL
1 0.09837735 0.12640121 0.13982546 0.10556982
2 0.02298923 0.02417428 0.02173655 0.02407456
3 0.02422377 0.02542536 0.03160567 0.04148048
4 0.02741970 0.04008005 0.07237725 0.03952874
5 0.20455348 0.17100359 0.11075895 0.16653569
6 0.15266426 0.07820994 0.06136150 0.16508883
# Step2: set up covariance matrix 
U.c = cov_canonical(dt_mash)  
print(names(U.c))
[1] "identity"      "beta_naive"    "beta_IF"       "beta_IFSL"    
[5] "beta_SL"       "equal_effects" "simple_het_1"  "simple_het_2" 
[9] "simple_het_3" 
# Step3: fit model 
m.c = mash(dt_mash, U.c)
 - Computing 15678 x 253 likelihood matrix.
 - Likelihood calculations took 2.52 seconds.
 - Fitting model with 253 mixture components.
 - Model fitting took 14.23 seconds.
 - Computing posterior matrices.
 - Computation allocated took 13.56 seconds.
# Step4: extract posterior summarize 

head(get_lfsr(m.c))   # local false sign rates
    beta_naive     beta_IF   beta_IFSL     beta_SL
1 1.461406e-05 0.001824021 0.004385345 0.002141932
2 1.876247e-04 0.099080350 0.099233110 0.099949419
3 3.520635e-05 0.016831278 0.016881393 0.018060472
4 2.629536e-03 0.495295005 0.494371262 0.468454622
5 4.657397e-04 0.001811972 0.001688937 0.001921296
6 7.303887e-02 0.855488753 0.873244307 0.858295958
head(get_pm(m.c))
   beta_naive      beta_IF    beta_IFSL      beta_SL
1 -0.24998712 -0.250345427 -0.243688943 -0.245792041
2 -0.04582012 -0.038363102 -0.038302041 -0.038231226
3 -0.05954638 -0.058071103 -0.058122522 -0.057942265
4  0.06609349  0.024188691  0.024158574  0.027910831
5 -0.26644629 -0.265655730 -0.264519032 -0.265028508
6 -0.19970374 -0.005753663 -0.002717302 -0.005782514
head(get_psd(m.c))
  beta_naive    beta_IF  beta_IFSL    beta_SL
1 0.05799366 0.06082965 0.06221880 0.05897826
2 0.01624149 0.01686986 0.01685286 0.01691490
3 0.01488694 0.01620381 0.01625526 0.01650750
4 0.02791045 0.02987130 0.03139002 0.03048489
5 0.07604640 0.07563894 0.07428845 0.07540395
6 0.13864721 0.02489209 0.02284952 0.02834736
head(get_significant_results(m.c))
 661 2075 2694 3191 3304 3305 
 661 2068 2687 3184 3297 3298 
print(length(get_significant_results(m.c)))
[1] 15450

Get sharing

print(get_pairwise_sharing(m.c, factor=0))
           beta_naive   beta_IF beta_IFSL   beta_SL
beta_naive  1.0000000 0.9922977 0.9803883 0.9858900
beta_IF     0.9922977 1.0000000 0.9977311 0.9984487
beta_IFSL   0.9803883 0.9977311 1.0000000 0.9989194
beta_SL     0.9858900 0.9984487 0.9989194 1.0000000
print(get_loglik(m.c))
[1] 39976.75

Estimate mixture proportion

print(get_estimated_pi(m.c))
         null      identity    beta_naive       beta_IF     beta_IFSL 
 0.0006367433  0.0000000000  0.2126963603  0.0000000000  0.0000000000 
      beta_SL equal_effects  simple_het_1  simple_het_2  simple_het_3 
 0.0000000000  0.7166936937  0.0000000000  0.0000000000  0.0699732027 
barplot(get_estimated_pi(m.c),las = 2)

Version Author Date
59bbc5e Nicholeyang0215 2019-11-21
mash_plot_meta(m.c,get_significant_results(m.c)[1])

Effect Size Comparison

Posterior Mean VS. Original Effect

par(mfrow = c(2,2))

for (i in c(1:4)){
  
  plot(dt_mash$Bhat[,i], get_pm(m.c)[,i], pch = 20, ylab = "Posterior Mean", xlab = "Original Effect", main = paste('Condition_',i, sep = ""))
  abline(coef = c(0,1), col = "red")
  
}

Scaled by standard deviation: Posterior Mean VS. Original Effect

par(mfrow = c(2,2))
for ( i in c(1:4)){
  
  plot(dt_mash$Bhat[,i]/dt_mash$Shat[,i], get_pm(m.c)[,i]/get_psd(m.c)[,i], pch = 20, ylab = "Posterior Mean", xlab = "Original Effect", main = paste('Condition_',i, sep = ""))
  abline(coef = c(0,1), col = "red")
  
}


sessionInfo()
R version 3.5.1 (2018-07-02)
Platform: x86_64-apple-darwin15.6.0 (64-bit)
Running under: macOS  10.15

Matrix products: default
BLAS: /Library/Frameworks/R.framework/Versions/3.5/Resources/lib/libRblas.0.dylib
LAPACK: /Library/Frameworks/R.framework/Versions/3.5/Resources/lib/libRlapack.dylib

locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] mashr_0.2.21.0641 ashr_2.2-38      

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.2        plyr_1.8.4        compiler_3.5.1   
 [4] later_1.0.0       git2r_0.26.1      highr_0.7        
 [7] workflowr_1.5.0   iterators_1.0.12  tools_3.5.1      
[10] digest_0.6.18     evaluate_0.13     lattice_0.20-38  
[13] rlang_0.4.0       Matrix_1.2-15     foreach_1.4.7    
[16] yaml_2.2.0        parallel_3.5.1    mvtnorm_1.0-11   
[19] xfun_0.4          stringr_1.4.0     knitr_1.21       
[22] fs_1.3.1          rprojroot_1.3-2   grid_3.5.1       
[25] glue_1.3.0        R6_2.4.0          rmarkdown_1.11   
[28] mixsqp_0.1-97     rmeta_3.0         magrittr_1.5     
[31] whisker_0.3-2     backports_1.1.3   promises_1.1.0   
[34] codetools_0.2-16  htmltools_0.4.0   MASS_7.3-51.1    
[37] assertthat_0.2.1  abind_1.4-5       httpuv_1.5.2     
[40] stringi_1.3.1     doParallel_1.0.15 pscl_1.5.2       
[43] truncnorm_1.0-8   SQUAREM_2017.10-1