7_normalization.Rmd

---
title: "Script 6: Normalization"
date: '`r format(Sys.time(), "%d %B, %Y")`'
output: html_document
---

```{r runtime start, include=FALSE}
start_time <- Sys.time()
```

```{r setup, include=FALSE}
source("../data/BMIQ_1.6_Teschendorff.R") # load script for BMIQ normalization 

needed_packages <- c("BiocManager","RPMM", "knitr", "dplyr", "data.table")
installed_packages <- needed_packages %in% rownames(installed.packages())
if (any(installed_packages == FALSE)) {
  install.packages(needed_packages[!installed_packages], repos = "http://cran.us.r-project.org")
}
lapply(needed_packages, library, character.only = TRUE)

if (!("minfi" %in% rownames(installed.packages()))) {
  BiocManager::install("minfi")
}
library(minfi)

user_choices <- readRDS("../data/user_choices.rds")
knitr::opts_knit$set(root.dir = paste0(user_choices$personal_path, "/"))
knitr::opts_chunk$set(echo = FALSE)

if (user_choices$array_type == "v2") {
  if (!("jokergoo/IlluminaHumanMethylationEPICv2manifest" %in% rownames(installed.packages()))) {
    BiocManager::install("jokergoo/IlluminaHumanMethylationEPICv2manifest")
  }
  if (!("IlluminaHumanMethylationEPICv2anno.20a1.hg38" %in% rownames(installed.packages()))) {
    BiocManager::install("jokergoo/IlluminaHumanMethylationEPICv2anno.20a1.hg38")
  }
  library(IlluminaHumanMethylationEPICv2manifest)
  library(IlluminaHumanMethylationEPICv2anno.20a1.hg38)
}
```

```{r load data, include=FALSE}
load(paste0(user_choices$project_name, "/processed_data/RGSet_clean.Rdata"))
load(paste0(user_choices$project_name, "/processed_data/Betas_clean.Rdata"))
load(paste0(user_choices$project_name, "/processed_data/PhenoData_clean.Rdata"))
```

# Description

This script:  

* annotates the probes  
* normalizes data with stratified quantile normalization 
(followed by BMIQ = beta-mixtrure quantile normalization) to minimize unwanted 
technique-related variation within and between samples  
* visualizes beta densities before and after normalization  
* creates two pdf files of beta densities plots per sample for raw and normalized  
data for further investigation. These files are saved to reports folder.  

<br>  
**Note**  
The user can further alter the normalization methods if needed (e.g. include noob etc.)  

```{r get annotation of probes, include=FALSE}
annotations_clean = getAnnotation(RGSet_clean)
save(annotations_clean, file = paste0(user_choices$project_name, "/reports/annotations_clean.Rdata"))
```

## Normalization of data performed

```{r normalize probes, include=FALSE}
RGSet_clean_quantile <- preprocessQuantile(RGSet_clean)
save(RGSet_clean_quantile, file = paste0(user_choices$project_name, 
                                         "/processed_data/RGSet_clean_quantile.Rdata")) # output: GenomicRatioSet

Betas_clean_quantile <- getBeta(RGSet_clean_quantile)
save(Betas_clean_quantile, file = paste0(user_choices$project_name, 
                                         "/processed_data/Betas_clean_quantile.Rdata"))
Mset_clean_qunatile <- getM(RGSet_clean_quantile)
save(Mset_clean_qunatile, file = paste0(user_choices$project_name, 
                                        "/processed_data/Mset_clean_qunatile.Rdata"))
# further normalization with BMIQ:
probeType <- as.data.frame(annotations_clean[rownames(Betas_clean_quantile),c("Name","Type")])
probeType$probeType = ifelse(probeType$Type %in% "I", 1, 2)
Betas_clean_quantile_bmiq <- apply(Betas_clean_quantile[,1:length(colnames(Betas_clean_quantile))],2,
                                   function(a) BMIQ(a,probeType$probeType,plots=FALSE)$nbeta) # sourced from script "BMIQ_1.6_Teschendorff.R"
save(Betas_clean_quantile_bmiq, file = paste0(user_choices$project_name,
                                              "/processed_data/Betas_clean_quantile_bmiq.Rdata"))
```

## Beta values distribution report

```{r beta values distribution}
densityPlot(Betas_clean, sampGroups = PhenoData_clean$Slide, legend = FALSE, 
            pal = "darkblue", main = "Raw Betas", xlab = "Beta Value")
densityPlot(Betas_clean_quantile, sampGroups = PhenoData_clean$Slide, legend = FALSE, 
            pal = "darkblue", main = "Quantile Adjusted Betas", xlab = "Beta Value")
densityPlot(Betas_clean_quantile_bmiq, sampGroups = PhenoData_clean$Slide, legend = FALSE, 
            pal = "darkblue", main = "Quantile-BMIQ Adjusted Betas", xlab = "Beta Value")
```

```{r, save reports as pdf, include=FALSE}
pdf(file = paste0(user_choices$project_name, 
                  "/reports/beta_distributions_raw_normalized.pdf"))
densityPlot(Betas_clean, sampGroups = PhenoData_clean$Slide, legend = FALSE, 
            pal = "darkblue", main = "Raw Betas", xlab = "Beta Value")
densityPlot(Betas_clean_quantile, sampGroups = PhenoData_clean$Slide, legend = FALSE, 
            pal = "darkblue", main = "Quantile Adjusted Betas", xlab = "Beta Value")
densityPlot(Betas_clean_quantile_bmiq, sampGroups = PhenoData_clean$Slide, legend = FALSE, 
            pal = "darkblue", main = "Quantile-BMIQ Adjusted Betas", xlab = "Beta Value")
dev.off()

# additional plots to look for outliers in distribution:
names_Betas <- colnames(Betas_clean)
pdf(file = paste0(user_choices$project_name, "/reports/beta_densities_raw.pdf"))
for (i in 1:ncol(Betas_clean)) {
  i_mat <- as.matrix(Betas_clean[ ,i])
  densityPlot(i_mat, pal = "darkblue", main = names_Betas[i])
}
dev.off()

names_quantileBetas <- colnames(Betas_clean_quantile)
pdf(paste0(user_choices$project_name, "/reports/beta_densities_quantile_normalized.pdf"))
for (i in 1:ncol(Betas_clean_quantile)) {
  i_mat <- as.matrix(Betas_clean_quantile[ ,i])
  name <- colnames(Betas_clean_quantile[,i])
  densityPlot(i_mat, pal = "darkblue", main = names_quantileBetas[i])
}
dev.off()
```

## User report

```{r, info output for user 1, results='asis'}
cat("Data underwent stratified quantile normalization followed by BMIQ and were saved to the processed data folder. ", 
    sep = "<br>\n")
if (length(which(is.nan(Betas_clean_quantile_bmiq))) == 0) {
  cat("There were no NAs after normalization", sep = "<br>\n")
} else {
  cat("NAs were produced during normalization, please re-check!", sep = "<br>\n")
}
```

```{r, info output for user 2, results='asis'}
cat("Session info text file was updated", sep = "<br>\n")
```

```{r, document session info into a text file, include=FALSE}
connection <- file(paste0(user_choices$personal_path, "/", user_choices$project_name, 
                          "/session_info_all.txt"), "a+")
writeLines("######################################################################", connection)
writeLines("############################  Script 6:  #############################", connection)
writeLines("######################################################################", connection)
sessioninfo <- sessionInfo()
writeLines("\nR Version:", connection)
writeLines(paste0("   ", sessioninfo$R.version$version.string), connection)
writeLines("\nAttached packages:", connection)
# nicely format packages (with version)
package_version <- unlist(lapply(sessioninfo$otherPkgs, function(x){paste0("   ",x$Package, " (", x$Version, ")")}))
names(package_version) <- NULL
for(i in 1:length(package_version)) {
  writeLines(package_version[i], connection)
}
writeLines("\n", connection)
close(connection)
```

```{r runtime end, include=FALSE}
end_time <- Sys.time()
run_time <- as.numeric(round((end_time - start_time), 1), units = "mins")
```

## Completion time

```{r, completion time, results = 'asis'}
cat("The time for the script to run was:", run_time, "minutes", sep = " ")
```