LSHTM_analysis/scripts/af_or_calcs.R

365 lines
11 KiB
R
Executable file

#!/usr/bin/env Rscript
#require('compare')
require('getopt', quietly=TRUE) # We need to be able to parse arguments
#########################################################
# TASK: To calculate Allele Frequency and
# Odds Ratio from master data
# and add the calculated params to meta_data extracted from
# data_extraction.py
#########################################################
#getwd()
setwd('~/git/LSHTM_analysis/scripts')
cat(c(getwd(),'\n'))
# Command line args
spec = matrix(c(
"drug" , "d", 1, "character",
"gene" , "g", 1, "character"
), byrow = TRUE, ncol = 4)
opt = getopt(spec);
drug = opt$drug
gene = opt$gene
if(is.null(drug)|is.null(gene)) {
stop('Missing arguments: --drug and --gene must both be specified (case-sensitive)')
}
#options(scipen = 999) #disabling scientific notation in R.
#%% variable assignment: input and output paths & filenames
gene_match = paste0(gene,'_p.')
cat(gene_match)
#=============
# directories
#=============
datadir = paste0('~/git/Data')
indir = paste0(datadir, '/', drug, '/', 'input')
outdir = paste0(datadir, '/', drug, '/', 'output')
#===========
# input
#===========
# input file 1: master data
#in_filename_master = 'original_tanushree_data_v2.csv' #19K
in_filename_master = 'mtb_gwas_meta_v3.csv' #33k
infile_master = paste0(datadir, '/', in_filename_master)
cat(paste0('Reading infile1: raw data', ' ', infile_master) )
# input file 2: gene associated meta data file to extract valid snps and add calcs to.
# This is outfile_metadata from data_extraction.py
in_filename_metadata = paste0(tolower(gene), '_metadata.csv')
infile_metadata = paste0(outdir, '/', in_filename_metadata)
cat(paste0('Reading input file 2 i.e gene associated metadata:', infile_metadata))
#===========
# output
#===========
#out_filename_af_or = paste0(tolower(gene), '_meta_data_with_AF_OR.csv')
out_filename_af_or = paste0(tolower(gene), '_af_or.csv')
outfile_af_or = paste0(outdir, '/', out_filename_af_or)
cat(paste0('Output file with full path:', outfile_af_or))
#%% end of variable assignment for input and output files
#########################################################
# 1: Read master/raw data stored in Data/
#########################################################
raw_data_all = read.csv(infile_master, stringsAsFactors = F)
# building cols to extract
dr_muts_col = paste0('dr_mutations_', drug)
other_muts_col = paste0('other_mutations_', drug)
cat('Extracting columns based on variables:\n'
, drug
, '\n'
, dr_muts_col
, '\n'
, other_muts_col
, '\n===============================================================')
raw_data = raw_data_all[,c("id"
, drug
, dr_muts_col
, other_muts_col)]
rm(raw_data_all)
rm(indir, in_filename_master, infile_master)
#===========
# 1a: exclude na
#===========
raw_data = raw_data[!is.na(raw_data[[drug]]),]
total_samples = length(unique(raw_data$id))
cat(paste0('Total samples without NA in', ' ', drug, 'is:', total_samples))
# sanity check: should be true
is.numeric(total_samples)
#===========
# 1b: combine the two mutation columns
#===========
all_muts_colname = paste0('all_mutations_', drug)
print(paste('New column added:', all_muts_colname))
#raw_data$all_mutations_pyrazinamide = paste(raw_data$dr_mutations_pyrazinamide, raw_data$other_mutations_pyrazinamide)
raw_data[[all_muts_colname]] = paste(raw_data[[dr_muts_col]], raw_data[[other_muts_col]])
head(raw_data[[all_muts_colname]])
#===========
# 1c: create yet another column that contains all the mutations but in lower case
#===========
head(raw_data[[all_muts_colname]])
raw_data$all_muts_gene = tolower(raw_data[[all_muts_colname]])
head(raw_data$all_muts_gene)
# sanity checks
#table(grepl("gene_p",raw_data$all_muts_gene))
cat(paste0('converting gene match:', gene_match, ' ', 'to lowercase'))
gene_match = tolower(gene_match)
table(grepl(gene_match,raw_data$all_muts_gene))
# sanity check: should be TRUE
#sum(table(grepl("gene_p",raw_data$all_muts_gene))) == total_samples
# sanity check
if(sum(table(grepl(gene_match, raw_data$all_muts_gene))) == total_samples){
cat('PASS: Total no. of samples match')
} else{
cat('FAIL: No. of samples mismatch')
}
#########################################################
# 2: Read valid snps for which OR
# can be calculated
#########################################################
cat(paste0('Reading gene associated metadata:', infile_metadata))
gene_metadata = read.csv(infile_metadata
#, file.choose()
, stringsAsFactors = F
, header = T)
# get just the variable name from variable
#deparse(substitute(myvar)
print(paste('Dim of', deparse(substitute(gene_metadata)), ':')); print(dim(gene_metadata))
# clear variables
rm(in_filename_metadata, infile_metadata)
# count na in drug column
tot_pza_na = sum(is.na(gene_metadata[[drug]]))
expected_rows = nrow(gene_metadata) - tot_pza_na
# drop na from the drug column
gene_snps_or = gene_metadata[!is.na(gene_metadata[[drug]]),]
# sanity check
if(nrow(gene_snps_or) == expected_rows){
cat('PASS: no. of rows match with expected_rows')
} else{
cat('FAIL: nrows mismatch.')
}
# extract unique snps to iterate over for AF and OR calcs
gene_snps_unique = unique(gene_snps_or$mutation)
cat(paste0('Total no. of distinct comp snps to perform OR calcs: ', length(gene_snps_unique)))
#===========================================================================================
#########################
# custom chisq function:
# To calculate OR
#########################
#i = "pnca_p.trp68gly"
i = "pnca_p.gly162asp"
mut = grepl(i,raw_data$all_muts_gene)
mut = as.numeric(mut)
dst = raw_data[[drug]]
#x = as.numeric(mut)
#y = dst
mychisq_or = function(x,y){
tab = as.matrix(table(x,y))
a = tab[2,2]
if (a==0){ a<-0.5}
b = tab[2,1]
if (b==0){ b<-0.5}
c = tab[1,2]
if (c==0){ c<-0.5}
d = tab[1,1]
if (d==0){ d<-0.5}
(a/b)/(c/d)
}
or_mychisq = mychisq_or(dst, mut)
print(paste0('mychisq OR:', or_mychisq ))
odds_fisher = fisher.test(table(dst, mut))$estimate
pval_fisher = fisher.test(table(dst, mut))$p.value
print(paste0('fisher OR:', odds_fisher))
print(paste0('fisher p-value:', pval_fisher))
model<-glm(dst ~ mut, family = binomial)
or_logistic = exp(summary(model)$coefficients[2,1])
print(paste0('logistic OR:', or_logistic))
pval_logistic = summary(model)$coefficients[2,4]
print(paste0('logistic pval:', pval_logistic))
#=====================================
#OR calcs using the following 4
#1) chisq.test
#2) fisher
#3) modified chisq.test
#4) logistic
#5) adjusted logistic?
#6) kinship (separate script)
#======================================
# TEST FOR a few muts: sapply and df
#===============================================
#snps <- gene_snps_unique[1:2]# reassign so you test with subset of muts
snps <- gene_snps_unique
cat(paste0('Running calculations for:', length(snps), ' nssnps\n'
, 'gene: ', gene
, '\ndrug: ', drug ))
# DV: <drug> 0 or 1
dst = raw_data[[drug]]
# initialise an empty df
ors_df = data.frame()
x = sapply(snps,function(m){
mut = grepl(m,raw_data$all_muts_gene)
mut = as.numeric(mut)
cat(paste0('Running mutation:', m, '\n'))
model<-glm(dst ~ mut, family = binomial)
#-------------------
# allele frequency
#-------------------
afs = mean(mut)
#-------------------
# logistic model
#-------------------
beta_logistic = summary(model)$coefficients[2,1]
or_logistic = exp(summary(model)$coefficients[2,1])
#print(paste0('logistic OR:', or_logistic))
pval_logistic = summary(model)$coefficients[2,4]
#print(paste0('logistic pval:', pval_logistic))
se_logistic = summary(model)$coefficients[2,2]
#print(paste0('logistic SE:', se_logistic))
zval_logistic = summary(model)$coefficients[2,3]
#print(paste0('logistic zval:', zval_logistic))
ci_mod = exp(confint(model))[2,]
#print(paste0('logistic CI:', ci_mod))
ci_lower_logistic = ci_mod[["2.5 %"]]
ci_upper_logistic = ci_mod[["97.5 %"]]
#-------------------
# custom_chisq and fisher: OR p-value and CI
#-------------------
or_mychisq = mychisq_or(dst, mut)
#print(paste0('mychisq OR:', or_mychisq))
odds_fisher = fisher.test(table(dst, mut))$estimate
or_fisher = odds_fisher[[1]]
pval_fisher = fisher.test(table(dst, mut))$p.value
ci_lower_fisher = fisher.test(table(dst, mut))$conf.int[1]
ci_upper_fisher = fisher.test(table(dst, mut))$conf.int[2]
#-------------------
# chi sq estimates
#-------------------
estimate_chisq = chisq.test(table(dst, mut))$statistic; estimate_chisq
est_chisq = estimate_chisq[[1]]; print(est_chisq)
pval_chisq = chisq.test(table(dst, mut))$p.value
# build a row to append to df
row = data.frame(mutation = m
, af = afs
, beta_logistic = beta_logistic
, or_logistic = or_logistic
, pval_logistic = pval_logistic
, se_logistic = se_logistic
, zval_logistic = zval_logistic
, ci_low_logistic = ci_lower_logistic
, ci_hi_logistic = ci_upper_logistic
, or_mychisq = or_mychisq
, or_fisher = or_fisher
, pval_fisher = pval_fisher
, ci_low_fisher= ci_lower_fisher
, ci_hi_fisher = ci_upper_fisher
, est_chisq = est_chisq
, pval_chisq = pval_chisq
)
#print(row)
ors_df <<- rbind(ors_df, row)
})
#%%======================================================
# Writing file with calculated ORs and AFs
cat(paste0('writing output file: '
, '\nFilen: ', outfile_af_or))
write.csv(ors_df, outfile_af_or
, row.names = F)
cat(paste0('Finished writing:'
, outfile_af_or
, '\nNo. of rows: ', nrow(ors_df)
, '\nNo. of cols: ', ncol(ors_df)))
#%%======================================================
cat('\n======sneak peek into a few muts with prominent or and p-vals=======\n')
cat(paste0('======================================='
, '\nmutation with highest logistic OR:'
, '\n=======================================\n'))
print(ors_df[which(ors_df$or_logistic == max(ors_df$or_logistic)),])
cat(paste0('======================================='
, '\nmutation with highest mychisq OR:'
, '\n=======================================\n'))
print(ors_df[which(ors_df$or_mychisq == max(ors_df$or_mychisq)),])
# gives too many due to Inf
#cat(paste0('======================================='
#, '\nmutation with highest fisher OR:'
#, '\n=======================================\n'))
#print(ors_df[which(ors_df$or_fisher == max(ors_df$or_fisher)),])
cat(paste0('======================================='
, '\nmutation with lowest logistic pval:'
, '\n=======================================\n'))
print(ors_df[which(ors_df$pval_logistic == min(ors_df$pval_logistic)),])
cat(paste0('======================================='
, '\nmutation with lowest fisher pval:'
, '\n=======================================\n'))
print(ors_df[which(ors_df$pval_fisher == min(ors_df$pval_fisher)),])
#**********************************************************
cat('End of script: calculated AF, OR, pvalues and saved file')
#**********************************************************