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Knit directory: rare-mutation-detection/

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Metrics for E. coli K12 data

MultiQC reports:

library(ggplot2)
library(data.table)
library(dplyr)
library(here)
library(tibble)
library(stringr)
library(Rsamtools)
library(GenomicRanges)
library(seqinr)
library(parallel)
library(readxl)
library(patchwork)
library(RColorBrewer)
library(UpSetR)
library(vcfR)
source(here('code/load_data.R'))
source(here('code/plot.R'))
source(here('code/efficiency_nanoseq_functions.R'))
# Ecoli genome max size
# genome_max <- 4528118
genome_max <- c('2e914854fabb46b9_1' = 4661751,
                '2e914854fabb46b9_2' = 67365)
cores = 8
genomeFile <- here('data/ref/Escherichia_coli_ATCC_10798.fasta')
rinfo_dir <- here('data/ecoli/AGRF_CAGRF22029764_HJK2GDSX3/QC/read_info')
markdup_dir <- here('data/ecoli/AGRF_CAGRF22029764_HJK2GDSX3/QC/mark_duplicates')
qualimap_dir <- here('data/ecoli/AGRF_CAGRF22029764_HJK2GDSX3/QC/qualimap')
qualimap_cons_dir <- here('data/ecoli/AGRF_CAGRF22029764_HJK2GDSX3/QC/consensus/qualimap')
qualimap_cons_nossc_dir <- here('data/ecoli/AGRF_CAGRF22029764_HJK2GDSX3/QC/consensus/qualimap_nossc')
metadata_file <- here('data/metadata/NovaSeq data E coli.xlsx')
variant_dir <- here('data/ecoli/AGRF_CAGRF22029764_HJK2GDSX3/variants')
variant_nossc_dir <- here('data/ecoli/AGRF_CAGRF22029764_HJK2GDSX3/variants_nossc')
sample_names <- list.files(rinfo_dir) %>%
                str_split('\\.txt.gz') %>%
                lapply(., dplyr::first) %>%
                unlist() %>%
                str_split('_') %>%
                lapply(., head, 2) %>%
                lapply(., paste, collapse='-') %>%
                unlist()

# load variant data
var_df <- load_variants(variant_dir, sample_names)
var_df_nossc <- load_variants(variant_nossc_dir, sample_names[-9])

# load and fetch duplicate rate from MarkDuplicates output
mdup <- load_markdup_data(markdup_dir, sample_names)

# get mean coverage for pre and post-consensus reads
qmap_cov <- get_qmap_coverage(qualimap_dir, sample_names)
qmap_cons_cov <- get_qmap_coverage(qualimap_cons_dir, sample_names)
qmap_cons_cov_nossc <- get_qmap_coverage(qualimap_cons_nossc_dir, sample_names[-9])

# uncomment below to calculate metrics
# # calculate metrics for nanoseq
# rlen <- 151; skips <- 5
# metrics_nano <- calc_metrics_new_rbs(rinfo_dir, pattern = 'Nano', cores = cores)
# 
# # calculate metrics for xGen
# rlen <- 151; skips <- 8
# metrics_xgen <- calc_metrics_new_rbs(rinfo_dir, pattern = 'xGEN', cores = cores)
# 
# metrics <- c(metrics_nano, metrics_xgen) %>% bind_rows()
# metrics$duplicate_rate <- as.numeric(mdup)
# metrics$duplex_coverage_ratio <- qmap_cov$coverage / qmap_cons_cov$coverage
# metrics$duplex_coverage_ratio[qmap_cons_cov$coverage < 1] <- 0 # fix when < 1 duplex cov
# metrics$sample <- gsub('-HJK2GDSX3', '', sample_names)

# cache metrics object
# saveRDS(metrics, file = here('data/metrics.rds'))
metrics <- readRDS(here('data/metrics.rds'))

# load metadata
metadata <- read_excel(metadata_file)
metadata$`sample name` <- gsub('_', '-', metadata$`sample name`)

# prepare for plotting
mm <- data.frame(melt(metrics))
mm$protocol <- 'NanoSeq'
mm$protocol[grep('xGEN', mm$sample)] <- 'xGen'

mm <- inner_join(mm, metadata, by=c('sample' = 'sample name'))
colnames(mm)[2] <- 'metric'
mm$nuclease <- paste(mm$`Mung bean unit`, mm$`S1 unit`, sep='+')

Metric comparison plots

Duplicate rate

Fraction of duplicate reads calculated by Picard’s MarkDuplicates. This is based on barcode-aware aligned duplicates mapping to the same 5’ positions for both read pairs. The NanoSeq Analysis pipeline states the optimal empirical duplicate rate is 75-76% (marked in the plot).

metric <- 'duplicate_rate'
ggplot(mm[mm$metric == metric,], aes(sample, value)) +
        geom_histogram(stat = 'identity', position = 'dodge') +
        theme_bw() +
        coord_flip() +
        geom_hline(yintercept = 0.81, alpha = 0.4)  +
        ggtitle(metric)

Version Author Date
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05

Fraction of singleton reads

Shows the number of single-read families divided by the total number of reads. As suggested by Stoler et al. 2016, this metric can server as a proxy for error rate, as (uncorrected) barcode mismatches will manifest as single-read families. The lower the fraction of singletons, the better.

metric <- 'frac_singletons'
ggplot(mm[mm$metric == metric,], aes(sample, value)) +
        geom_histogram(stat = 'identity', position = 'dodge') +
        theme_bw() +
        coord_flip() +
        ggtitle(metric)

Version Author Date
a860101 Marek Cmero 2022-04-06
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05

Drop-out rate

This is the same calculation as F-EFF in the NanoSeq Analysis pipeline:

“This shows the fraction of read bundles missing one of the two original strands beyond what would be expected under random sampling (assuming a binomial process). Good values are between 0.10-0.30, and larger values are likely due to DNA damage such as modified bases or internal nicks that prevent amplification of one of the two strands. Larger values do not impact the quality of the results, just reduce the efficiency of the protocol.”

This is similar to the singleton fraction, but taking into account loss of pairs due to sampling. The optimal range is shown by the lines.

metric <- 'drop_out_rate'
ggplot(mm[mm$metric == metric,], aes(sample, value)) +
        geom_histogram(stat = 'identity', position = 'dodge') +
        theme_bw() +
        coord_flip() +
        geom_hline(yintercept = c(0.1, 0.3), alpha = 0.4)  +
        ggtitle(metric)

Version Author Date
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05

Efficiency

Efficiency is the number of duplex bases divided by the number of sequenced bases. According the NanoSeq Analysis pipeline, this value is maximised at ~0.07 when duplicate rates and strand drop-outs are optimal.

metric <- 'efficiency'
ggplot(mm[mm$metric == metric,], aes(sample, value)) +
        geom_histogram(stat = 'identity', position = 'dodge') +
        theme_bw() +
        coord_flip() +
        geom_hline(yintercept = c(0.07), alpha = 0.4)  +
        ggtitle(metric)

Version Author Date
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05

GC deviation

GC deviation is the absolute difference between GC_BOTH and GC_SINGLE calculated by the NanoSeq Analysis pipeline. The lower this deviation, the better.

“GC_BOTH and GC_SINGLE: the GC content of RBs with both strands and with just one strand. The two values should be similar between them and similar to the genome average. If there are large deviations that is possibly due to biases during PCR amplification. If GC_BOTH is substantially larger than GC_SINGLE, DNA denaturation before dilution may have taken place.”

metric <- 'gc_deviation'
ggplot(mm[mm$metric == metric,], aes(sample, value)) +
        geom_histogram(stat = 'identity', position = 'dodge') +
        theme_bw() +
        coord_flip() +
        ggtitle(metric)

Version Author Date
faf9130 Marek Cmero 2022-05-18
4da2244 Marek Cmero 2022-05-11
cc380cc Marek Cmero 2022-05-11
7c4f403 Marek Cmero 2022-04-25
fcb6578 Marek Cmero 2022-04-11
a2f0a4a Marek Cmero 2022-04-08
c246dc2 Marek Cmero 2022-04-07
a860101 Marek Cmero 2022-04-06
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05

Duplex Coverage ratio

The mean sequence (pre-duplex) coverage divided by mean duplex coverage. Indicates the yield of how much duplex coverage we get at each sample’s sequence coverage. Abascal et al. report that their yield was approximately 30x (marked on the plot).

metric <- 'duplex_coverage_ratio'
ggplot(mm[mm$metric == metric,], aes(sample, value)) +
        geom_histogram(stat = 'identity', position = 'dodge') +
        theme_bw() +
        coord_flip() +
        geom_hline(yintercept = 30, alpha = 0.4)  +
        ggtitle(metric)

Version Author Date
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05

Family statistics

Comparison of family pair sizes between samples (these are calculated from total reads of paired AB and BA families).

ggplot(mm[mm$metric %like% 'family', ], aes(value, sample, colour = metric)) +
        geom_point() +
        coord_trans(x='log2') +
        scale_x_continuous(breaks=seq(0, 94, 8)) +
        theme(axis.text.x = element_text(size=5)) +
        theme_bw() +
        ggtitle('Family pair sizes')

Version Author Date
fcb6578 Marek Cmero 2022-04-11

The following plot shows:

  • families_gt1: number of family pairs where at least one family (AB or BA) has > 1 reads.
  • paired_families: number of family pairs where both families (AB and BA) have > 0 reads.
  • paired_and_gt1: number of family pairs where both families (AB and BA) have > 1 reads.
ggplot(mm[mm$metric %like% 'pair|gt1', ], aes(value, sample, fill = metric)) +
        geom_bar(stat='identity', position='dodge') +
        theme_bw() +
        ggtitle('Family statistics')

Version Author Date
fcb6578 Marek Cmero 2022-04-11

Compare metrics side-by-side

Compare protocols and nucleases directly.

gg_prot <- list(geom_boxplot(outlier.shape = NA),
               geom_jitter(width = 0.1, size = 2, aes(colour = nuclease, shape = nuclease)),
               theme_bw(),
               theme(legend.position = 'left'))
gg_nuc <- list(geom_boxplot(outlier.shape = NA),
               geom_jitter(width = 0.1, size = 2, aes(colour = protocol, shape = protocol)),
               theme_bw(),
               theme(legend.position = 'right'))

# duplicate rate
metric <- 'duplicate_rate'
p1 <- ggplot(mm[mm$metric == metric,], aes(protocol, value)) +
        gg_prot + geom_hline(yintercept = 0.81) +
        ggtitle('Duplicate rate (line = optimal)')

p2 <- ggplot(mm[mm$metric == metric,], aes(nuclease, value)) +
        gg_nuc + geom_hline(yintercept = 0.81) +
        ggtitle('Duplicate rate (line = optimal)')
show(p1 + p2)

Version Author Date
fcb6578 Marek Cmero 2022-04-11
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05
# singletons
metric <- 'frac_singletons'
p1 <- ggplot(mm[mm$metric == metric,], aes(protocol, value)) +
        gg_prot +
        ggtitle('Fraction of singleton reads')

p2 <- ggplot(mm[mm$metric == metric,], aes(nuclease, value)) +
        gg_nuc + 
        ggtitle('Fraction of singleton reads')
show(p1 + p2)

Version Author Date
fcb6578 Marek Cmero 2022-04-11
a860101 Marek Cmero 2022-04-06
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05
# drop-out rate
metric <- 'drop_out_rate'
p1 <- ggplot(mm[mm$metric == metric,], aes(protocol, value)) +
        gg_prot + geom_hline(yintercept = c(0.1, 0.3)) + ylim(c(0,1)) +
        ggtitle('Drop-out fraction\n(lines = optimal range)')

p2 <- ggplot(mm[mm$metric == metric,], aes(nuclease, value)) +
        gg_nuc + geom_hline(yintercept = c(0.1, 0.3)) + ylim(c(0,1)) +
        ggtitle('Drop-out fraction\n(lines = optimal range)')
show(p1 + p2)

Version Author Date
fcb6578 Marek Cmero 2022-04-11
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05
# efficiency
metric <- 'efficiency'
p1 <- ggplot(mm[mm$metric == metric,], aes(protocol, value)) +
        gg_prot + geom_hline(yintercept = 0.07) +
        ggtitle('Efficiency\n(line = optimal)')

p2 <- ggplot(mm[mm$metric == metric,], aes(nuclease, value)) +
        gg_nuc + geom_hline(yintercept = 0.07) +
        ggtitle('Efficiency\n(line = optomal)')
show(p1 + p2)

Version Author Date
cc380cc Marek Cmero 2022-05-11
fcb6578 Marek Cmero 2022-04-11
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05
# GC deviation
metric <- 'gc_deviation'
p1 <- ggplot(mm[mm$metric == metric,], aes(protocol, value)) +
        gg_prot +
        ggtitle('GC deviation\n(both strands vs. one)')

p2 <- ggplot(mm[mm$metric == metric,], aes(nuclease, value)) +
        gg_nuc + 
        ggtitle('GC deviation\n(both strands vs. one)')
show(p1 + p2)

Version Author Date
faf9130 Marek Cmero 2022-05-18
4da2244 Marek Cmero 2022-05-11
cc380cc Marek Cmero 2022-05-11
7c4f403 Marek Cmero 2022-04-25
fcb6578 Marek Cmero 2022-04-11
a2f0a4a Marek Cmero 2022-04-08
c246dc2 Marek Cmero 2022-04-07
a860101 Marek Cmero 2022-04-06
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05
# duplex coverage ratio
metric <- 'duplex_coverage_ratio'
p1 <- ggplot(mm[mm$metric == metric,], aes(protocol, value)) +
        gg_prot + geom_hline(yintercept = 30) +
        ggtitle('Duplex coverage ratio\n(total cov / duplex cov)')

p2 <- ggplot(mm[mm$metric == metric,], aes(nuclease, value)) +
        gg_nuc + geom_hline(yintercept = 30) +
        ggtitle('Duplex coverage ratio\n(total cov / duplex cov)')
show(p1 + p2)

Version Author Date
fcb6578 Marek Cmero 2022-04-11
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05
metric_optimals <- list('duplicate_rate' = 0.81,
                          'frac_singletons' = 0,
                          'drop_out_rate' = c(0.1, 0.3),
                          'efficiency' = 0.07,
                          'gc_deviation' = 0,
                          'duplex_coverage_ratio' = 30)
                       
gg_prot <- list(geom_boxplot(outlier.shape = NA),
                geom_jitter(width = 0.1, size = 2, aes(colour = nuclease, shape = nuclease)),
                theme_bw(),
                theme(legend.position = 'bottom'))
gg_nuc <- list(geom_boxplot(outlier.shape = NA),
               geom_jitter(width = 0.1, size = 2, aes(colour = protocol, shape = protocol)),
               theme_bw(),
               theme(legend.position = 'bottom'))

for(metric in names(metric_optimals)) {
    threshold <- metric_optimals[metric][[1]]
    tmp <- mm[mm$metric == metric & !(mm$sample == 'xGEN-xGEN' & mm$replicate == 1),]
    p1 <- ggplot(tmp, aes(sample, value)) +
        geom_point() +
        theme_bw() +
        coord_flip() +
        geom_hline(yintercept = threshold, alpha = 0.4) 
    
    p2 <- ggplot(tmp, aes(protocol, value)) +
        gg_prot + geom_hline(yintercept = threshold, alpha = 0.4) 
    
    p3 <- ggplot(tmp, aes(nuclease, value)) +
        gg_nuc + geom_hline(yintercept = threshold, alpha = 0.4) 
    
    show(p1 + p2 + p3)
}
ggplot(mm[mm$metric %like% 'pair|gt1', ], aes(value, sample, fill = metric)) +
        geom_bar(stat='identity', position='dodge') +
        theme_bw() +
        scale_fill_brewer(palette = 'Dark2') +
        theme(legend.position = 'bottom')
mt <- mm
mt$replicate <- str_split(mt$sample, 'Rep') %>% lapply(., dplyr::last) %>% unlist() %>% as.numeric()
mt$sample <- str_split(mt$sample, 'Rep') %>% lapply(., dplyr::first) %>% unlist()

mt <- mt[,c('sample', 'metric', 'value', 'protocol', 'nuclease', 'replicate')]
dm <- reshape2::dcast(mt, sample + protocol + nuclease + replicate ~ metric)

cols <- c(brewer.pal(5, 'Greens')[2:5],
          brewer.pal(6, 'Blues')[2:6])
names(cols) <- as.factor(dm$sample) %>% levels()

p1 <- ggplot(dm, aes(efficiency, duplicate_rate, colour=sample)) +
    geom_point() +
    theme_bw() +
    scale_colour_manual(values = cols) +
    ggtitle('Efficiency vs. duplicate rate')

p2 <- ggplot(dm, aes(efficiency, drop_out_rate, colour=sample)) +
    geom_point() +
    theme_bw() +
    scale_colour_manual(values = cols) +
    ggtitle('Efficiency vs. drop-out rate')
show(p1 + p2)

Facet summary plots

Facet boxplots by nuclease and protocol to show overall results.

ggplot(mm, aes(protocol, value)) + 
    geom_boxplot() +
    theme_bw() +
    facet_wrap(~metric, scales = 'free') +
    ggtitle('by protocol')

Version Author Date
faf9130 Marek Cmero 2022-05-18
4da2244 Marek Cmero 2022-05-11
cc380cc Marek Cmero 2022-05-11
ggplot(mm, aes(nuclease, value)) + 
    geom_boxplot() +
    theme_bw() +
    facet_wrap(~metric, scales = 'free') +
    ggtitle('by nuclease')

Version Author Date
faf9130 Marek Cmero 2022-05-18
4da2244 Marek Cmero 2022-05-11
cc380cc Marek Cmero 2022-05-11

Plots again removing the outlier xGEN rep 1.

mmo <- mm[mm$sample != 'xGEN-xGENRep1',]
mmo$replicate <- str_split(mmo$sample, 'Rep') %>% lapply(., dplyr::last) %>% unlist() %>% as.numeric()
mmo$sample <- str_split(mmo$sample, 'Rep') %>% lapply(., dplyr::first) %>% unlist()

ggplot(mmo, aes(protocol, value)) + 
    geom_boxplot() +
    theme_bw() +
    facet_wrap(~metric, scales = 'free') +
    ggtitle('by protocol')

Version Author Date
faf9130 Marek Cmero 2022-05-18
4da2244 Marek Cmero 2022-05-11
cc380cc Marek Cmero 2022-05-11
ggplot(mmo, aes(nuclease, value)) + 
    geom_boxplot() +
    theme_bw() +
    facet_wrap(~metric, scales = 'free') +
    ggtitle('by nuclease')

Version Author Date
faf9130 Marek Cmero 2022-05-18
4da2244 Marek Cmero 2022-05-11
cc380cc Marek Cmero 2022-05-11

Summary plot including separated by all experimental factors.

ggplot(mmo, aes(sample, value, colour = protocol, shape = nuclease)) + 
    geom_point() +
    theme_bw() +
    theme(axis.text.x = element_text(angle = 90)) +
    facet_wrap(~metric, scales = 'free') +
    scale_colour_brewer(palette = 'Dark2') +
    ggtitle('by protocol')

Version Author Date
faf9130 Marek Cmero 2022-05-18
4da2244 Marek Cmero 2022-05-11

Statistical test results by protocol

For each metric, take the average of each replicate and perform a two-sided, unpaired T-test between protocols.

stats <- NULL
metric_names <- unique(mm$metric) %>% as.character()
for(metric_name in metric_names) {
    nano <- mm[mm$metric == metric_name & mm$protocol == 'NanoSeq',]
    xgen <- mm[mm$metric == metric_name & mm$protocol == 'xGen',]
    nano_vals <- data.table(nano)[, mean(value), by = nuclease]$V1
    xgen_vals <- data.table(xgen)[, mean(value), by = nuclease]$V1
    wtest <- t.test(nano_vals, xgen_vals)
    stats <- rbind(stats,
                   data.frame(metric = metric_name, pvalue = wtest$p.value))
}
stats$significant <- stats$pvalue < 0.05
print(stats)
                  metric       pvalue significant
1        frac_singletons 0.3509205995       FALSE
2             efficiency 0.0016455448        TRUE
3          drop_out_rate 0.0016563300        TRUE
4           gc_deviation 0.0195493871        TRUE
5            family_mean 0.2739786956       FALSE
6          family_median 0.3816330944       FALSE
7             family_max 0.4142481163       FALSE
8           families_gt1 0.6326687504       FALSE
9        paired_families 0.0006261990        TRUE
10        paired_and_gt1 0.0003304955        TRUE
11        duplicate_rate 0.9225366816       FALSE
12 duplex_coverage_ratio 0.3166974439       FALSE

Rerun tests removing outlier (xGEN rep1). The results are similar.

stats <- NULL
for(metric_name in metric_names) {
    nano <- mmo[mmo$metric == metric_name & mmo$protocol == 'NanoSeq',]
    xgen <- mmo[mmo$metric == metric_name & mmo$protocol == 'xGen',]
    nano_vals <- data.table(nano)[, mean(value), by = nuclease]$V1
    xgen_vals <- data.table(xgen)[, mean(value), by = nuclease]$V1
    wtest <- t.test(nano_vals, xgen_vals)
    stats <- rbind(stats,
                   data.frame(metric = metric_name, pvalue = wtest$p.value))
}
stats$significant <- stats$pvalue < 0.05
print(stats)
                  metric      pvalue significant
1        frac_singletons 0.885668764       FALSE
2             efficiency 0.017624387        TRUE
3          drop_out_rate 0.010803300        TRUE
4           gc_deviation 0.002863331        TRUE
5            family_mean 0.408145893       FALSE
6          family_median 0.617803978       FALSE
7             family_max 0.517858472       FALSE
8           families_gt1 0.914651102       FALSE
9        paired_families 0.001878931        TRUE
10        paired_and_gt1 0.002903205        TRUE
11        duplicate_rate 0.469189762       FALSE
12 duplex_coverage_ratio 0.214507629       FALSE

Two-way ANOVA analysis

We consider a two-way ANOVA, modelling the protocol, Mung Bean Unit and S1 Unit variables, as well as the interaction effect between the units and the protocol.

stats <- NULL
metric_names <- unique(mm$metric) %>% as.character()
for(metric_name in metric_names) {
    x <- mm[mm$metric == metric_name,]
    x$MungBeanUnit <- as.factor(x$`Mung bean unit`)
    x$S1Unit <- as.factor(x$`S1 unit`)
    x <- x[,c('MungBeanUnit', 'S1Unit', 'protocol', 'nuclease', 'value')]
    x_aov <- aov(value ~ MungBeanUnit * protocol + S1Unit * protocol, data = x) %>% summary() %>% dplyr::first()
    stats <- rbind(stats,
                   data.frame(metric = metric_name,
                              variable = rownames(x_aov)[1:5],
                              pvalue = x_aov[['Pr(>F)']][1:5]))
}
stats$significant <- stats$pvalue < 0.05
print(stats)
                  metric              variable       pvalue significant
1        frac_singletons MungBeanUnit          0.3179447536       FALSE
2        frac_singletons protocol              0.9702278541       FALSE
3        frac_singletons S1Unit                0.8553539457       FALSE
4        frac_singletons MungBeanUnit:protocol 0.9858376372       FALSE
5        frac_singletons protocol:S1Unit       0.8540792709       FALSE
6             efficiency MungBeanUnit          0.6743588660       FALSE
7             efficiency protocol              0.0033776091        TRUE
8             efficiency S1Unit                0.4674622674       FALSE
9             efficiency MungBeanUnit:protocol 0.8509682597       FALSE
10            efficiency protocol:S1Unit       0.2278366157       FALSE
11         drop_out_rate MungBeanUnit          0.4118682293       FALSE
12         drop_out_rate protocol              0.0002566346        TRUE
13         drop_out_rate S1Unit                0.0904262242       FALSE
14         drop_out_rate MungBeanUnit:protocol 0.8387881526       FALSE
15         drop_out_rate protocol:S1Unit       0.3182162279       FALSE
16          gc_deviation MungBeanUnit          0.5321833114       FALSE
17          gc_deviation protocol              0.0087584727        TRUE
18          gc_deviation S1Unit                0.7094314628       FALSE
19          gc_deviation MungBeanUnit:protocol 0.4019325303       FALSE
20          gc_deviation protocol:S1Unit       0.9145680596       FALSE
21           family_mean MungBeanUnit          0.3721341384       FALSE
22           family_mean protocol              0.2541550650       FALSE
23           family_mean S1Unit                0.2914711924       FALSE
24           family_mean MungBeanUnit:protocol 0.2723545197       FALSE
25           family_mean protocol:S1Unit       0.1501250836       FALSE
26         family_median MungBeanUnit          0.6347857947       FALSE
27         family_median protocol              0.4810155294       FALSE
28         family_median S1Unit                0.3250056081       FALSE
29         family_median MungBeanUnit:protocol 0.4997581250       FALSE
30         family_median protocol:S1Unit       0.3250056081       FALSE
31            family_max MungBeanUnit          0.3849414781       FALSE
32            family_max protocol              0.5270991535       FALSE
33            family_max S1Unit                0.1424841525       FALSE
34            family_max MungBeanUnit:protocol 0.9819905871       FALSE
35            family_max protocol:S1Unit       0.0605658200       FALSE
36          families_gt1 MungBeanUnit          0.1793349230       FALSE
37          families_gt1 protocol              0.9876271265       FALSE
38          families_gt1 S1Unit                0.6881757434       FALSE
39          families_gt1 MungBeanUnit:protocol 0.6170001142       FALSE
40          families_gt1 protocol:S1Unit       0.0301632029        TRUE
41       paired_families MungBeanUnit          0.3217761699       FALSE
42       paired_families protocol              0.0002319573        TRUE
43       paired_families S1Unit                0.1990511038       FALSE
44       paired_families MungBeanUnit:protocol 0.9226482412       FALSE
45       paired_families protocol:S1Unit       0.8092463937       FALSE
46        paired_and_gt1 MungBeanUnit          0.6527042939       FALSE
47        paired_and_gt1 protocol              0.0007082361        TRUE
48        paired_and_gt1 S1Unit                0.8872835419       FALSE
49        paired_and_gt1 MungBeanUnit:protocol 0.5304733713       FALSE
50        paired_and_gt1 protocol:S1Unit       0.2688705912       FALSE
51        duplicate_rate MungBeanUnit          0.3209743574       FALSE
52        duplicate_rate protocol              0.6617113407       FALSE
53        duplicate_rate S1Unit                0.4855983121       FALSE
54        duplicate_rate MungBeanUnit:protocol 0.8160371321       FALSE
55        duplicate_rate protocol:S1Unit       0.5516726318       FALSE
56 duplex_coverage_ratio MungBeanUnit          0.0515969116       FALSE
57 duplex_coverage_ratio protocol              0.0059993368        TRUE
58 duplex_coverage_ratio S1Unit                0.4875101164       FALSE
59 duplex_coverage_ratio MungBeanUnit:protocol 0.0621558351       FALSE
60 duplex_coverage_ratio protocol:S1Unit       0.0041291841        TRUE

We remove the outlier xGEN rep 1 and test again.

stats <- NULL
metric_names <- unique(mmo$metric) %>% as.character()
for(metric_name in metric_names) {
    x <- mmo[mmo$metric == metric_name,]
    x$MungBeanUnit <- as.factor(x$`Mung bean unit`)
    x$S1Unit <- as.factor(x$`S1 unit`)
    x <- x[,c('MungBeanUnit', 'S1Unit', 'protocol', 'nuclease', 'value')]
    x_aov <- aov(value ~ MungBeanUnit * protocol + S1Unit * protocol, data = x) %>% summary() %>% dplyr::first()
    stats <- rbind(stats,
                   data.frame(metric = metric_name,
                              variable = rownames(x_aov)[1:5],
                              pvalue = x_aov[['Pr(>F)']][1:5]))
}
stats$significant <- stats$pvalue < 0.05
print(stats)
                  metric              variable       pvalue significant
1        frac_singletons MungBeanUnit          3.747242e-01       FALSE
2        frac_singletons protocol              6.061218e-01       FALSE
3        frac_singletons S1Unit                2.820185e-02        TRUE
4        frac_singletons MungBeanUnit:protocol 1.145001e-01       FALSE
5        frac_singletons protocol:S1Unit       2.714409e-02        TRUE
6             efficiency MungBeanUnit          2.943575e-02        TRUE
7             efficiency protocol              8.567087e-07        TRUE
8             efficiency S1Unit                4.375525e-02        TRUE
9             efficiency MungBeanUnit:protocol 2.583454e-01       FALSE
10            efficiency protocol:S1Unit       3.175014e-03        TRUE
11         drop_out_rate MungBeanUnit          4.996962e-04        TRUE
12         drop_out_rate protocol              2.459532e-09        TRUE
13         drop_out_rate S1Unit                2.501322e-05        TRUE
14         drop_out_rate MungBeanUnit:protocol 9.115253e-02       FALSE
15         drop_out_rate protocol:S1Unit       1.679681e-03        TRUE
16          gc_deviation MungBeanUnit          5.973605e-02       FALSE
17          gc_deviation protocol              1.140481e-04        TRUE
18          gc_deviation S1Unit                4.637927e-01       FALSE
19          gc_deviation MungBeanUnit:protocol 5.772604e-02       FALSE
20          gc_deviation protocol:S1Unit       8.311211e-01       FALSE
21           family_mean MungBeanUnit          4.646379e-01       FALSE
22           family_mean protocol              8.429941e-02       FALSE
23           family_mean S1Unit                1.077790e-01       FALSE
24           family_mean MungBeanUnit:protocol 6.294463e-02       FALSE
25           family_mean protocol:S1Unit       3.389191e-02        TRUE
26         family_median MungBeanUnit          4.629868e-01       FALSE
27         family_median protocol              3.164774e-01       FALSE
28         family_median S1Unit                1.678507e-01       FALSE
29         family_median MungBeanUnit:protocol 2.615312e-01       FALSE
30         family_median protocol:S1Unit       1.678507e-01       FALSE
31            family_max MungBeanUnit          8.985047e-01       FALSE
32            family_max protocol              4.901973e-01       FALSE
33            family_max S1Unit                1.144701e-01       FALSE
34            family_max MungBeanUnit:protocol 9.783491e-01       FALSE
35            family_max protocol:S1Unit       4.537604e-02        TRUE
36          families_gt1 MungBeanUnit          4.921202e-01       FALSE
37          families_gt1 protocol              9.709211e-01       FALSE
38          families_gt1 S1Unit                3.554965e-01       FALSE
39          families_gt1 MungBeanUnit:protocol 1.121914e-01       FALSE
40          families_gt1 protocol:S1Unit       2.152397e-04        TRUE
41       paired_families MungBeanUnit          1.158679e-02        TRUE
42       paired_families protocol              2.650844e-08        TRUE
43       paired_families S1Unit                1.825979e-03        TRUE
44       paired_families MungBeanUnit:protocol 4.727076e-01       FALSE
45       paired_families protocol:S1Unit       4.522724e-01       FALSE
46        paired_and_gt1 MungBeanUnit          3.715875e-01       FALSE
47        paired_and_gt1 protocol              4.877137e-07        TRUE
48        paired_and_gt1 S1Unit                7.110938e-01       FALSE
49        paired_and_gt1 MungBeanUnit:protocol 4.055773e-02        TRUE
50        paired_and_gt1 protocol:S1Unit       1.317773e-02        TRUE
51        duplicate_rate MungBeanUnit          2.028567e-01       FALSE
52        duplicate_rate protocol              9.553308e-02       FALSE
53        duplicate_rate S1Unit                1.519542e-02        TRUE
54        duplicate_rate MungBeanUnit:protocol 7.348826e-02       FALSE
55        duplicate_rate protocol:S1Unit       3.151836e-02        TRUE
56 duplex_coverage_ratio MungBeanUnit          2.480884e-01       FALSE
57 duplex_coverage_ratio protocol              6.668694e-04        TRUE
58 duplex_coverage_ratio S1Unit                3.194763e-01       FALSE
59 duplex_coverage_ratio MungBeanUnit:protocol 1.030421e-02        TRUE
60 duplex_coverage_ratio protocol:S1Unit       4.306854e-04        TRUE

Relationships between variables

mm$replicate <- str_split(mm$sample, 'Rep') %>% lapply(., dplyr::last) %>% unlist() %>% as.numeric()
mm$sample <- str_split(mm$sample, 'Rep') %>% lapply(., dplyr::first) %>% unlist()

mm <- mm[,c('sample', 'metric', 'value', 'protocol', 'nuclease', 'replicate')]
dm <- reshape2::dcast(mm, sample + protocol + nuclease + replicate ~ metric)

cols <- c(brewer.pal(5, 'Greens')[2:5],
          brewer.pal(6, 'Blues')[2:6])
names(cols) <- as.factor(dm$sample) %>% levels()

ggplot(dm, aes(frac_singletons, drop_out_rate, colour=sample)) +
    geom_point() +
    theme_bw() +
    scale_colour_manual(values = cols) +
    ggtitle('Singletons vs. drop-out rate')

Version Author Date
a860101 Marek Cmero 2022-04-06
ggplot(dm, aes(efficiency, duplicate_rate, colour=sample)) +
    geom_point() +
    theme_bw() +
    scale_colour_manual(values = cols) +
    ggtitle('Efficiency vs. duplicate rate')

Version Author Date
a860101 Marek Cmero 2022-04-06
ggplot(dm, aes(efficiency, drop_out_rate, colour=sample)) +
    geom_point() +
    theme_bw() +
    scale_colour_manual(values = cols) +
    ggtitle('Efficiency vs. drop-out rate')

Version Author Date
a860101 Marek Cmero 2022-04-06
ggplot(dm, aes(efficiency, duplex_coverage_ratio, colour=sample)) +
    geom_point() +
    theme_bw() +
    scale_colour_manual(values = cols) +
    ggtitle('Efficiency vs. duplex coverage ratio')

Version Author Date
a860101 Marek Cmero 2022-04-06
ggplot(dm, aes(duplicate_rate, duplex_coverage_ratio, colour=sample)) +
    geom_point() +
    theme_bw() +
    scale_colour_manual(values = cols) +
    ggtitle('Duplicate rate vs. duplex coverage ratio')

Version Author Date
a860101 Marek Cmero 2022-04-06

Variant calls

Upset plot showing duplex variant calls. Variants were called in areas with at least 4x coverage with at least 2 supporting reads and a VAF of \(\geq2\).

ulist <- NULL
for(sample in sample_names) {
    ids <- var_df[var_df$sample %in% sample,]$id
    if (length(ids) > 0) {
        ulist[[gsub(pattern = '-HJK2GDSX3', replacement = '', sample)]] <- ids
    }
}

upset(fromList(ulist), order.by='freq', nsets=length(sample_names))

Version Author Date
7c4f403 Marek Cmero 2022-04-25
a2f0a4a Marek Cmero 2022-04-08
c246dc2 Marek Cmero 2022-04-07

Duplex coverage without requiring SSC

The pipeline was run only requiring a single read on each strand. Here we plot the difference in mean coverage. As we would expect, skipping SSC step increases duplex coverage. For some samples with disproportionately higher single-read families (NanoMB-S1), this increases duplex coverage significantly more.

ccov <- inner_join(qmap_cons_cov,
                   qmap_cons_cov_nossc,
                   by = 'Sample',
                   suffix = c('_ssc', '_nossc')) %>%
          inner_join(., qmap_cov, by = 'Sample')
ccov$sample <- str_split(ccov$Sample, 'Rep') %>% lapply(., dplyr::first) %>% unlist()
ccov$duplex_cov_ratio <- ccov$coverage / ccov$coverage_ssc
ccov$duplex_cov_ratio_noscc <- ccov$coverage / ccov$coverage_nossc

p1 <- ggplot(ccov, aes(coverage_ssc, coverage_nossc, colour = sample)) +
  geom_point() +
  theme_bw() +
  xlim(0, 550) +
  ylim(0, 550) +
  xlab('with SSC') +
  ylab('without SSC') +
  geom_abline(slope = 1) +
  theme(legend.position = 'left') +
  scale_colour_brewer(palette = 'Dark2') +
  ggtitle('Mean duplex coverage')

p2 <- ggplot(ccov, aes(duplex_cov_ratio, duplex_cov_ratio_noscc, colour = sample)) +
  geom_point() +
  theme_bw() +
  xlim(0, 100) +
  ylim(0, 100) +
  xlab('with SSC') +
  ylab('without SSC') +
  geom_abline(slope = 1) +
  theme(legend.position = 'right') +
  scale_colour_brewer(palette = 'Dark2') +
  ggtitle('Duplex coverage ratio')

p1 + p2

Version Author Date
faf9130 Marek Cmero 2022-05-18

Variant calls without SSC

Here we show the variant calls from the duplex sequences without SSC in the same Upset plot format.

for(sample in sample_names) {
    ids <- var_df_nossc[var_df_nossc$sample %in% sample,]$id
    if (length(ids) > 0) {
        ulist[[sample]] <- ids
    }
}

upset(fromList(ulist), order.by='freq', nsets=length(sample_names))

Version Author Date
faf9130 Marek Cmero 2022-05-18

Input cells

Estimate the number of input cells using formula \(d / e / c = n\) where d = mean duplex coverage, e = duplex efficiency, c = coverage per genome equivalent and n = number of cells.

coverage_per_genome <- 10
qmap_cons_cov$Sample <- gsub('-HJK2GDSX3', '', qmap_cons_cov$Sample)
metrics <- inner_join(metrics, qmap_cons_cov, by = c('sample' = 'Sample'))
metrics$estimated_cells <- metrics$coverage / metrics$efficiency / coverage_per_genome

ggplot(metrics[!metrics$sample %in% 'xGEN-xGENRep1',], aes(sample, estimated_cells)) +
    geom_bar(stat = 'identity') + 
    theme_minimal() +
    coord_flip()

Version Author Date
22d32ef Marek Cmero 2022-05-31
b524238 Marek Cmero 2022-05-26
cc380cc Marek Cmero 2022-05-11
7c4f403 Marek Cmero 2022-04-25
fcb6578 Marek Cmero 2022-04-11
a2f0a4a Marek Cmero 2022-04-08
c246dc2 Marek Cmero 2022-04-07
a860101 Marek Cmero 2022-04-06
81272b2 Marek Cmero 2022-04-05
f13e13a Marek Cmero 2022-04-05
def2130 Marek Cmero 2022-04-05
953b83e Marek Cmero 2022-03-31
05412f6 Marek Cmero 2022-03-28

sessionInfo()
R version 4.0.5 (2021-03-31)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: CentOS Linux 7 (Core)

Matrix products: default
BLAS:   /stornext/System/data/apps/R/R-4.0.5/lib64/R/lib/libRblas.so
LAPACK: /stornext/System/data/apps/R/R-4.0.5/lib64/R/lib/libRlapack.so

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              
 [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    
 [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
 [7] LC_PAPER=en_US.UTF-8       LC_NAME=C                 
 [9] LC_ADDRESS=C               LC_TELEPHONE=C            
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       

attached base packages:
[1] stats4    parallel  stats     graphics  grDevices utils     datasets 
[8] methods   base     

other attached packages:
 [1] vcfR_1.12.0          UpSetR_1.4.0         RColorBrewer_1.1-3  
 [4] patchwork_1.1.1      readxl_1.3.1         seqinr_4.2-8        
 [7] Rsamtools_2.6.0      Biostrings_2.58.0    XVector_0.30.0      
[10] GenomicRanges_1.42.0 GenomeInfoDb_1.26.7  IRanges_2.24.1      
[13] S4Vectors_0.28.1     BiocGenerics_0.36.1  stringr_1.4.0       
[16] tibble_3.1.7         here_1.0.1           dplyr_1.0.7         
[19] data.table_1.14.0    ggplot2_3.3.6        workflowr_1.6.2     

loaded via a namespace (and not attached):
 [1] nlme_3.1-152           bitops_1.0-7           fs_1.5.0              
 [4] rprojroot_2.0.2        tools_4.0.5            bslib_0.3.0           
 [7] utf8_1.2.2             R6_2.5.1               vegan_2.5-7           
[10] DBI_1.1.1              mgcv_1.8-35            colorspace_2.0-3      
[13] permute_0.9-5          ade4_1.7-18            withr_2.5.0           
[16] tidyselect_1.1.1       gridExtra_2.3          compiler_4.0.5        
[19] git2r_0.28.0           cli_3.3.0              labeling_0.4.2        
[22] sass_0.4.0             scales_1.2.0           digest_0.6.29         
[25] rmarkdown_2.11         pkgconfig_2.0.3        htmltools_0.5.2       
[28] highr_0.9              fastmap_1.1.0          rlang_1.0.2           
[31] rstudioapi_0.13        jquerylib_0.1.4        generics_0.1.1        
[34] farver_2.1.0           jsonlite_1.7.2         BiocParallel_1.24.1   
[37] RCurl_1.98-1.3         magrittr_2.0.3         GenomeInfoDbData_1.2.4
[40] Matrix_1.3-2           Rcpp_1.0.7             munsell_0.5.0         
[43] fansi_1.0.3            ape_5.5                lifecycle_1.0.1       
[46] stringi_1.7.5          whisker_0.4            yaml_2.2.1            
[49] MASS_7.3-53.1          zlibbioc_1.36.0        plyr_1.8.6            
[52] pinfsc50_1.2.0         grid_4.0.5             promises_1.2.0.1      
[55] crayon_1.5.1           lattice_0.20-44        splines_4.0.5         
[58] knitr_1.33             pillar_1.7.0           reshape2_1.4.4        
[61] glue_1.6.2             evaluate_0.14          memuse_4.2-1          
[64] vctrs_0.4.1            httpuv_1.6.3           cellranger_1.1.0      
[67] gtable_0.3.0           purrr_0.3.4            assertthat_0.2.1      
[70] xfun_0.22              later_1.3.0            viridisLite_0.4.0     
[73] cluster_2.1.2          ellipsis_0.3.2