wf-transcriptomes-v202/bin/run_bambu.R
2026-05-05 14:10:04 +00:00

450 lines
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R
Executable File

#!/usr/bin/env Rscript
# Set seed for reproducibility
set.seed(42)
suppressPackageStartupMessages({
library(argparser)
library(bambu)
library(Rsamtools)
library(SummarizedExperiment)
library(jsonlite)
})
parser <- arg_parser("Run bambu transcript discovery and quantification.")
parser <- add_argument(parser, "--bam_dir", help = "Directory containing BAM files.")
parser <- add_argument(parser, "--bam_path", help = "Path to a single BAM file.")
parser <- add_argument(parser, "--sample_alias", help = "Alias to use for a single BAM file.")
parser <- add_argument(parser, "--sample_sheet", help = "Optional sample sheet CSV.")
parser <- add_argument(parser, "--annotation", help = "Reference annotation GTF/GFF.")
parser <- add_argument(parser, "--genome", help = "Reference genome FASTA.")
parser <- add_argument(parser, "--transcriptome_mode", help = "discover or fixed_annotation.", default = "discover")
parser <- add_argument(parser, "--threads", help = "Number of worker threads.", type = "numeric", default = 1)
parser <- add_argument(parser, "--ndr", help = "Optional novel discovery rate.", type = "numeric")
parser <- add_argument(parser, "--out_dir", help = "Output directory.")
argv <- parse_args(parser)
arg_missing <- function(value) {
if (is.null(value) || length(value) == 0 || all(is.na(value))) {
return(TRUE)
}
if (is.character(value)) {
return(all(!nzchar(value)))
}
FALSE
}
required_args <- c("annotation", "genome", "out_dir")
missing_args <- required_args[vapply(required_args, function(arg_name) {
value <- argv[[arg_name]]
arg_missing(value)
}, logical(1))]
if (length(missing_args) > 0) {
stop(sprintf(
"Missing required arguments: %s",
paste(sprintf("--%s", missing_args), collapse = ", ")
))
}
if (arg_missing(argv$bam_dir) == arg_missing(argv$bam_path)) {
stop("Provide exactly one of --bam_dir or --bam_path.")
}
dir.create(argv$out_dir, showWarnings = FALSE, recursive = TRUE)
sample_df <- NULL
if (!arg_missing(argv$sample_sheet)) {
sample_df <- read.csv(argv$sample_sheet, check.names = FALSE, stringsAsFactors = FALSE)
if (!"alias" %in% names(sample_df)) {
stop("Sample sheet must contain an 'alias' column.")
}
}
strip_alias <- function(path) {
name <- basename(path)
name <- sub("\\.aligned\\.sorted\\.bam$", "", name)
name <- tools::file_path_sans_ext(name)
name
}
if (!arg_missing(argv$bam_dir)) {
bam_paths <- sort(list.files(argv$bam_dir, pattern = "\\.bam$", full.names = TRUE))
if (length(bam_paths) < 1) {
stop("No BAM files were found in bam_dir.")
}
aliases <- vapply(bam_paths, strip_alias, character(1))
} else {
bam_paths <- argv$bam_path
aliases <- if (!arg_missing(argv$sample_alias)) argv$sample_alias else strip_alias(argv$bam_path)
}
if (!is.null(sample_df)) {
missing_aliases <- setdiff(aliases, sample_df$alias)
if (length(missing_aliases) > 0) {
stop(sprintf(
"Sample sheet is missing alias rows for BAM files: %s",
paste(missing_aliases, collapse = ", ")
))
}
sample_df <- sample_df[match(aliases, sample_df$alias), , drop = FALSE]
} else {
sample_df <- data.frame(alias = aliases, stringsAsFactors = FALSE)
}
annotation_obj <- prepareAnnotations(argv$annotation)
reads <- if (length(bam_paths) == 1) bam_paths else BamFileList(bam_paths, yieldSize = 1000000)
# Handle NDR parameter with validation and documentation
default_ndr <- 0.1
ndr_value <- default_ndr
if (!arg_missing(argv$ndr)) {
if (argv$ndr < 0 || argv$ndr > 1) {
stop("NDR (Novel Discovery Rate) must be between 0 and 1")
}
ndr_value <- argv$ndr
message(sprintf("Using user-specified NDR = %.3f", ndr_value))
} else {
message(sprintf("Using default NDR = %.3f", default_ndr))
}
if (identical(argv$transcriptome_mode, "discover")) {
message("Novel Discovery Rate (NDR) controls transcript discovery stringency:")
message(" Lower NDR (e.g., 0.05) = fewer false positive transcripts, may miss real ones")
message(" Higher NDR (e.g., 0.2) = more sensitive discovery, more false positives")
message(sprintf(" Current NDR = %.3f balances precision and recall", ndr_value))
}
bambu_args <- list(
reads = reads,
annotations = annotation_obj,
genome = argv$genome,
ncore = as.integer(argv$threads),
discovery = identical(argv$transcriptome_mode, "discover")
)
if (identical(argv$transcriptome_mode, "discover")) {
bambu_args$NDR <- ndr_value
}
message("Running bambu...")
se <- do.call(bambu, bambu_args)
message("Bambu completed successfully")
colnames(se) <- aliases
counts_mat <- assays(se)$counts
full_length_mat <- assays(se)$fullLengthCounts
# Collect QC statistics before filtering
qc_stats <- list()
qc_stats$total_transcripts_before_filter <- nrow(se)
qc_stats$total_genes_before_filter <- length(unique(rowData(se)$GENEID))
qc_stats$samples <- ncol(se)
# Filter low-count transcripts
if (is.null(full_length_mat)) {
keep_idx <- rowSums(counts_mat) > 0
} else {
keep_idx <- rowSums(full_length_mat) > 0
}
if (!any(keep_idx)) {
keep_idx <- rowSums(counts_mat) >= 0
}
qc_stats$transcripts_filtered <- sum(!keep_idx)
message(sprintf("Filtering: keeping %d / %d transcripts", sum(keep_idx), length(keep_idx)))
se <- se[keep_idx, ]
# Library size statistics and warnings
lib_sizes <- colSums(assays(se)$counts)
qc_stats$library_sizes <- as.list(lib_sizes)
qc_stats$min_library_size <- min(lib_sizes)
qc_stats$max_library_size <- max(lib_sizes)
qc_stats$median_library_size <- median(lib_sizes)
if (length(lib_sizes) > 1) {
lib_size_ratio <- max(lib_sizes) / min(lib_sizes)
qc_stats$library_size_ratio <- lib_size_ratio
if (lib_size_ratio > 3) {
warning(sprintf(
"Large library size variation detected (%.1fx difference).\n Min: %d, Max: %d reads.\n CPM normalization may not be appropriate for such variation.",
lib_size_ratio, min(lib_sizes), max(lib_sizes)
))
qc_stats$library_size_warning <- sprintf("%.1fx variation (>3x threshold)", lib_size_ratio)
}
}
# Per-sample detection statistics
qc_stats$transcripts_detected_per_sample <- as.list(colSums(assays(se)$counts > 0))
qc_stats$median_transcripts_detected <- median(colSums(assays(se)$counts > 0))
qc_stats$total_transcripts_after_filter <- nrow(se)
qc_stats$total_genes_after_filter <- length(unique(rowData(se)$GENEID))
row_ranges <- rowRanges(se)
writeToGTF(row_ranges, file = file.path(argv$out_dir, "transcripts.gtf"))
gene_se <- transcriptToGeneExpression(se)
colnames(gene_se) <- aliases
saveRDS(se, file.path(argv$out_dir, "bambu_transcripts.rds"))
saveRDS(gene_se, file.path(argv$out_dir, "bambu_genes.rds"))
write.csv(sample_df, file.path(argv$out_dir, "samples.csv"), row.names = FALSE, quote = FALSE)
tx_meta <- as.data.frame(rowData(se))
if (!"TXNAME" %in% names(tx_meta)) {
tx_meta$TXNAME <- rownames(se)
}
if (!"GENEID" %in% names(tx_meta)) {
tx_meta$GENEID <- NA_character_
}
gene_meta <- as.data.frame(rowData(gene_se))
if (!"GENEID" %in% names(gene_meta)) {
gene_meta$GENEID <- rownames(gene_se)
}
matrix_to_df <- function(se_obj, assay_name, id_col, meta_df) {
assay_df <- as.data.frame(assays(se_obj)[[assay_name]])
assay_df[[id_col]] <- rownames(se_obj)
assay_df <- assay_df[, c(id_col, setdiff(names(assay_df), id_col)), drop = FALSE]
merge(meta_df, assay_df, by.x = id_col, by.y = id_col, all.y = TRUE, sort = FALSE)
}
normalise_tsv_value <- function(value) {
if (length(value) == 0 || all(is.na(value))) {
return(NA_character_)
}
if (is.list(value)) {
value <- unlist(value, recursive = TRUE, use.names = FALSE)
}
if (length(value) == 0 || all(is.na(value))) {
return(NA_character_)
}
paste(as.character(value), collapse = ";")
}
normalise_tsv_df <- function(df) {
as.data.frame(
lapply(df, function(column) {
if (is.list(column)) {
vapply(column, normalise_tsv_value, character(1))
} else {
column
}
}),
stringsAsFactors = FALSE,
check.names = FALSE
)
}
extract_gtf_attribute <- function(attr_field, key) {
match <- regexec(sprintf('%s "([^"]*)";', key), attr_field, perl = TRUE)
captures <- regmatches(attr_field, match)[[1]]
if (length(captures) < 2) {
return(NULL)
}
captures[2]
}
normalise_gtf_attribute_value <- function(value) {
if (is.null(value)) {
return(NULL)
}
value <- gsub('[";]', "", value)
value <- trimws(gsub("\\s+", " ", value))
if (!nzchar(value)) {
return(NULL)
}
value
}
sanitise_gtf_file <- function(path) {
lines <- readLines(path, warn = FALSE)
cleaned_lines <- vapply(lines, function(line) {
if (!nzchar(line) || startsWith(line, "#")) {
return(line)
}
fields <- strsplit(line, "\t", fixed = TRUE)[[1]]
if (length(fields) < 9) {
return(line)
}
attr_field <- fields[9]
transcript_id <- normalise_gtf_attribute_value(
extract_gtf_attribute(attr_field, "transcript_id")
)
gene_id <- normalise_gtf_attribute_value(
extract_gtf_attribute(attr_field, "gene_id")
)
if (!is.null(gene_id) && grepl("\\btranscript_id\\b", gene_id)) {
gene_id <- transcript_id
}
if (is.null(gene_id)) {
gene_id <- transcript_id
}
if (!is.null(gene_id)) {
attr_field <- sub(
'gene_id "([^"]*)";',
sprintf('gene_id "%s";', gene_id),
attr_field,
perl = TRUE
)
}
if (!is.null(transcript_id)) {
attr_field <- sub(
'transcript_id "([^"]*)";',
sprintf('transcript_id "%s";', transcript_id),
attr_field,
perl = TRUE
)
}
fields[9] <- attr_field
paste(fields, collapse = "\t")
}, character(1))
writeLines(cleaned_lines, path)
}
tx_meta <- normalise_tsv_df(tx_meta)
gene_meta <- normalise_tsv_df(gene_meta)
write.table(
tx_meta,
file = file.path(argv$out_dir, "transcript_metadata.tsv"),
sep = "\t",
quote = FALSE,
row.names = FALSE
)
write.table(
gene_meta,
file = file.path(argv$out_dir, "gene_metadata.tsv"),
sep = "\t",
quote = FALSE,
row.names = FALSE
)
tx_counts <- matrix_to_df(se, "counts", "TXNAME", tx_meta)
tx_cpm <- matrix_to_df(se, "CPM", "TXNAME", tx_meta)
gene_counts <- matrix_to_df(gene_se, "counts", "GENEID", gene_meta)
gene_cpm <- matrix_to_df(gene_se, "CPM", "GENEID", gene_meta)
write.table(
tx_counts,
file = file.path(argv$out_dir, "transcript_counts.tsv"),
sep = "\t",
quote = FALSE,
row.names = FALSE
)
write.table(
tx_cpm,
file = file.path(argv$out_dir, "transcript_cpm.tsv"),
sep = "\t",
quote = FALSE,
row.names = FALSE
)
write.table(
gene_counts,
file = file.path(argv$out_dir, "gene_counts.tsv"),
sep = "\t",
quote = FALSE,
row.names = FALSE
)
write.table(
gene_cpm,
file = file.path(argv$out_dir, "gene_cpm.tsv"),
sep = "\t",
quote = FALSE,
row.names = FALSE
)
sanitise_gtf_file(file.path(argv$out_dir, "transcripts.gtf"))
# Write QC statistics as JSON for HTML report
qc_stats$transcriptome_mode <- argv$transcriptome_mode
qc_stats$ndr_used <- if (identical(argv$transcriptome_mode, "discover")) ndr_value else "N/A"
qc_stats$timestamp <- format(Sys.time(), "%Y-%m-%d %H:%M:%S")
write_json(
qc_stats,
file.path(argv$out_dir, "bambu_qc_stats.json"),
pretty = TRUE,
auto_unbox = TRUE
)
format_count <- function(value) {
if (length(value) == 0 || all(is.na(value))) {
return("NA")
}
format(
round(as.numeric(value), 0),
scientific = FALSE,
trim = TRUE,
big.mark = ","
)
}
# Write human-readable QC summary
qc_summary <- c(
"Bambu Quantification QC Summary",
"================================",
"",
sprintf("Timestamp: %s", qc_stats$timestamp),
sprintf("Mode: %s", argv$transcriptome_mode),
if (identical(argv$transcriptome_mode, "discover")) sprintf("NDR: %.3f", ndr_value) else NULL,
"",
"Sample Statistics:",
sprintf(" Samples analyzed: %s", format_count(qc_stats$samples)),
sprintf(
" Median library size: %s reads",
format_count(qc_stats$median_library_size)
),
sprintf(
" Library size range: %s - %s reads",
format_count(qc_stats$min_library_size),
format_count(qc_stats$max_library_size)
),
if (!is.null(qc_stats$library_size_warning)) sprintf(" WARNING: %s", qc_stats$library_size_warning) else NULL,
"",
"Transcript Discovery:",
sprintf(
" Transcripts before filtering: %s",
format_count(qc_stats$total_transcripts_before_filter)
),
sprintf(
" Transcripts after filtering: %s",
format_count(qc_stats$total_transcripts_after_filter)
),
sprintf(
" Transcripts removed: %s",
format_count(qc_stats$transcripts_filtered)
),
sprintf(
" Median transcripts detected per sample: %s",
format_count(qc_stats$median_transcripts_detected)
),
"",
"Gene-Level Summary:",
sprintf(
" Unique genes (before filter): %s",
format_count(qc_stats$total_genes_before_filter)
),
sprintf(
" Unique genes (after filter): %s",
format_count(qc_stats$total_genes_after_filter)
),
""
)
writeLines(qc_summary, file.path(argv$out_dir, "bambu_qc_summary.txt"))
message("QC statistics written to bambu_qc_stats.json and bambu_qc_summary.txt")
# Save session info for reproducibility
writeLines(capture.output(sessionInfo()), file.path(argv$out_dir, "session_info.txt"))
message("Session info saved for reproducibility")