fastp

RNA-Seq

Trimming

Quality control

Description

An ultra-fast all-in-one FASTQ preprocessor (QC/adapters/trimming/filtering/splitting/merging...).

Features:

comprehensive quality profiling for both before and after filtering data (quality curves, base contents, KMER, Q20/Q30, GC Ratio, duplication, adapter contents...)
filter out bad reads (too low quality, too short, or too many N...)
cut low quality bases for per read in its 5' and 3' by evaluating the mean quality from a sliding window (like Trimmomatic but faster).
trim all reads in front and tail
cut adapters. Adapter sequences can be automatically detected, which means you don't have to input the adapter sequences to trim them.
correct mismatched base pairs in overlapped regions of paired end reads, if one base is with high quality while the other is with ultra low quality
trim polyG in 3' ends, which is commonly seen in NovaSeq/NextSeq data. Trim polyX in 3' ends to remove unwanted polyX tailing (i.e. polyA tailing for mRNA-Seq data)
preprocess unique molecular identifier (UMI) enabled data, shift UMI to sequence name.
report JSON format result for further interpreting.
visualize quality control and filtering results on a single HTML page (like FASTQC but faster and more informative).
split the output to multiple files (0001.R1.gz, 0002.R1.gz...) to support parallel processing. Two modes can be used, limiting the total split file number, or limitting the lines of each split file.
support long reads (data from PacBio / Nanopore devices).
support reading from STDIN and writing to STDOUT
support interleaved input
support ultra-fast FASTQ-level deduplication

Inputs

Name	Type & Properties	Description
--in1 -i	file required	Input FastQ file. Must be single-end or paired-end R1. Can be gzipped.
--in2 -I	file	Input FastQ file. Must be paired-end R2. Can be gzipped.

Name

Type & Properties

--in1

-i

file

required

--in2

-I

file

Outputs

Name	Type & Properties	Description
--out1 -o	file required output	The single-end or paired-end R1 reads that pass QC. Will be gzipped if its file name ends with `.gz`.
--out2 -O	file output	The paired-end R2 reads that pass QC. Will be gzipped if its file name ends with `.gz`.
--unpaired1	file output	Store the reads that `read1` passes filters but its paired `read2` doesn't.
--unpaired2	file output	Store the reads that `read2` passes filters but its paired `read1` doesn't.
--failed_out	file output	Store the reads that fail filters. If one read failed and is written to --failed_out, its failure reason will be appended to its read name. For example, failed_quality_filter, failed_too_short etc. For PE data, if unpaired reads are not stored (by giving --unpaired1 or --unpaired2), the failed pair of reads will be put together. If one read passes the filters but its pair doesn't, the failure reason will be paired_read_is_failing.
--overlapped_out	file output	For each read pair, output the overlapped region if it has no any mismatched base.

Name

Type & Properties

--out1

-o

file

required

output

--out2

-O

file

output

--unpaired1

file

output

--unpaired2

file

output

--failed_out

file

output

--overlapped_out

file

output

Report output arguments

Name	Type & Properties	Description
--json -j	file output	The json format report file name
--html	file output	The html format report file name
--report_title	string	The title of the html report, default is "fastp report".

Name

Type & Properties

--json

-j

file

output

--html

file

output

--report_title

string

Adapter trimming

Name	Type & Properties	Description
--disable_adapter_trimming -A	boolean_true	Disable adapter trimming.
--detect_adapter_for_pe	boolean_true	By default, the auto-detection for adapter is for SE data input only, turn on this option to enable it for PE data.
--adapter_sequence -a	string	The adapter sequences to be trimmed. For SE data, if not specified, the adapters will be auto-detected. For PE data, this is used if R1/R2 are found not overlapped
--adapter_sequence_r2	string	The adapter sequences to be trimmed for R2. This is used for PE data if R1/R2 are found overlapped.
--adapter_fasta	file	A FASTA file containing all the adapter sequences to be trimmed. For SE data, if not specified, the adapters will be auto-detected. For PE data, this is used if R1/R2 are found not overlapped.

Name

Type & Properties

--disable_adapter_trimming

-A

boolean_true

--detect_adapter_for_pe

boolean_true

--adapter_sequence

-a

string

--adapter_sequence_r2

string

--adapter_fasta

file

Base trimming

Name	Type & Properties	Description
--trim_front1 -f	integer	Trimming how many bases in front for read1, default is 0.
--trim_tail1 -t	integer	Trimming how many bases in tail for read1, default is 0.
--max_len1 -b	integer	If read1 is longer than max_len1, then trim read1 at its tail to make it as long as max_len1. Default 0 means no limitation.
--trim_front2 -F	integer	Trimming how many bases in front for read2, default is 0.
--trim_tail2 -T	integer	Trimming how many bases in tail for read2, default is 0.
--max_len2 -B	integer	If read2 is longer than max_len2, then trim read2 at its tail to make it as long as max_len2. Default 0 means no limitation.

Name

Type & Properties

--trim_front1

-f

integer

--trim_tail1

-t

integer

--max_len1

-b

integer

--trim_front2

-F

integer

--trim_tail2

-T

integer

--max_len2

-B

integer

Merging mode

Name	Type & Properties	Description
--merge -m	boolean_true	For paired-end input, merge each pair of reads into a single read if they are overlapped. The merged reads will be written to the file given by --merged_out, the unmerged reads will be written to the files specified by --out1 and --out2. The merging mode is disabled by default.
--merged_out	file output	In the merging mode, specify the file name to store merged output, or specify --stdout to stream the merged output.
--include_unmerged	boolean_true	In the merging mode, write the unmerged or unpaired reads to the file specified by --merge. Disabled by default.

Name

Type & Properties

--merge

-m

boolean_true

--merged_out

file

output

--include_unmerged

boolean_true

Additional input arguments

Name	Type & Properties	Description
--interleaved_in	boolean_true	Indicate that <in1> is an interleaved FASTQ which contains both read1 and read2. Disabled by default.
--fix_mgi_id	boolean_true	The MGI FASTQ ID format is not compatible with many BAM operation tools, enable this option to fix it.
--phred64 -6	boolean_true	Indicate the input is using phred64 scoring (it'll be converted to phred33, so the output will still be phred33)

Name

Type & Properties

--interleaved_in

boolean_true

--fix_mgi_id

boolean_true

--phred64

-6

boolean_true

Additional output arguments

Name	Type & Properties	Description
--compression -z	integer	Compression level for gzip output (1 ~ 9). 1 is fastest, 9 is smallest, default is 4.
--dont_overwrite	boolean_true	Don't overwrite existing files. Overwritting is allowed by default.

Name

Type & Properties

--compression

-z

integer

--dont_overwrite

boolean_true

Logging arguments

Name	Type & Properties	Description
--verbose -V	boolean_true	Output verbose log information (i.e. when every 1M reads are processed).

Name

Type & Properties

--verbose

-V

boolean_true

Processing arguments

Name	Type & Properties	Description
--reads_to_process	long	Specify how many reads/pairs to be processed. Default 0 means process all reads.

Name

Type & Properties

--reads_to_process

long

Deduplication arguments

Name	Type & Properties	Description
--dedup	boolean_true	Enable deduplication to drop the duplicated reads/pairs
--dup_calc_accuracy	integer	Accuracy level to calculate duplication (1~6). Higher level uses more memory (1G, 2G, 4G, 8G, 16G, 24G). Default 1 for no-dedup mode, and 3 for dedup mode.
--dont_eval_duplication	boolean_true	Don't evaluate duplication rate to save time and use less memory.

Name

Type & Properties

--dedup

boolean_true

--dup_calc_accuracy

integer

--dont_eval_duplication

boolean_true

PolyG tail trimming arguments

Name	Type & Properties	Description
--trim_poly_g -g	boolean_true	Force polyG tail trimming, by default trimming is automatically enabled for Illumina NextSeq/NovaSeq data
--poly_g_min_len	integer	The minimum length to detect polyG in the read tail. 10 by default.
--disable_trim_poly_g -G	boolean_true	Disable polyG tail trimming, by default trimming is automatically enabled for Illumina NextSeq/NovaSeq data

Name

Type & Properties

--trim_poly_g

-g

boolean_true

--poly_g_min_len

integer

--disable_trim_poly_g

-G

boolean_true

PolyX tail trimming arguments

Name	Type & Properties	Description
--trim_poly_x -x	boolean_true	Enable polyX trimming in 3' ends.
--poly_x_min_len	integer	The minimum length to detect polyX in the read tail. 10 by default.

Name

Type & Properties

--trim_poly_x

-x

boolean_true

--poly_x_min_len

integer

Cut arguments

Name	Type & Properties	Description
--cut_front -5	integer	Move a sliding window from front (5') to tail, drop the bases in the window if its mean quality < threshold, stop otherwise.
--cut_tail -3	integer	Move a sliding window from tail (3') to front, drop the bases in the window if its mean quality < threshold, stop otherwise.
--cut_right -r	integer	Move a sliding window from front to tail, if meet one window with mean quality < threshold, drop the bases in the window and the right part, and then stop.
--cut_window_size -W	integer	The window size option shared by cut_front, cut_tail or cut_sliding. Range: 1~1000, default: 4.
--cut_mean_quality -M	integer	The mean quality requirement option shared by cut_front, cut_tail or cut_sliding. Range: 1~36 default: 20 (Q20)
--cut_front_window_size	integer	The window size option of cut_front, default to cut_window_size if not specified.
--cut_front_mean_quality	integer	The mean quality requirement option of cut_front, default to cut_mean_quality if not specified.
--cut_tail_window_size	integer	The window size option of cut_tail, default to cut_window_size if not specified.
--cut_tail_mean_quality	integer	The mean quality requirement option of cut_tail, default to cut_mean_quality if not specified.
--cut_right_window_size	integer	The window size option of cut_right, default to cut_window_size if not specified.
--cut_right_mean_quality	integer	The mean quality requirement option of cut_right, default to cut_mean_quality if not specified.

Name

Type & Properties

--cut_front

-5

integer

--cut_tail

-3

integer

--cut_right

-r

integer

--cut_window_size

-W

integer

--cut_mean_quality

-M

integer

--cut_front_window_size

integer

--cut_front_mean_quality

integer

--cut_tail_window_size

integer

--cut_tail_mean_quality

integer

--cut_right_window_size

integer

--cut_right_mean_quality

integer

Quality filtering arguments

Name	Type & Properties	Description
--disable_quality_filtering -Q	boolean_true	Quality filtering is enabled by default. If this option is specified, quality filtering is disabled.
--qualified_quality_phred -q	integer	The quality value that a base is qualified. Default 15 means phred quality >=Q15 is qualified.
--unqualified_percent_limit -u	integer	How many percents of bases are allowed to be unqualified (0~100). Default 40 means 40%.
--n_base_limit -n	integer	If one read's number of N base is >n_base_limit, then this read/pair is discarded. Default is 5.
--average_qual -e	integer	If one read's average quality score <avg_qual, then this read/pair is discarded. Default 0 means no requirement.

Name

Type & Properties

--disable_quality_filtering

-Q

boolean_true

--qualified_quality_phred

-q

integer

--unqualified_percent_limit

-u

integer

--n_base_limit

-n

integer

--average_qual

-e

integer

Length filtering arguments

Name	Type & Properties	Description
--disable_length_filtering -L	boolean_true	Length filtering is enabled by default. If this option is specified, length filtering is disabled.
--length_required -l	integer	Reads shorter than length_required will be discarded, default is 15.
--length_limit	integer	Reads longer than length_limit will be discarded, default 0 means no limitation.

Name

Type & Properties

--disable_length_filtering

-L

boolean_true

--length_required

-l

integer

--length_limit

integer

Low complexity filtering arguments

Name	Type & Properties	Description
--low_complexity_filter -y	boolean_true	Enable low complexity filter. The complexity is defined as the percentage of base that is different from its next base (base[i] != base[i+1]).
--complexity_threshold -Y	integer	The threshold for low complexity filter (0~100). Default is 30, which means 30% complexity is required.

Name

Type & Properties

--low_complexity_filter

-y

boolean_true

--complexity_threshold

-Y

integer

Index filtering arguments

Name	Type & Properties	Description
--filter_by_index1	file	Specify a file contains a list of barcodes of index1 to be filtered out, one barcode per line.
--filter_by_index2	file	Specify a file contains a list of barcodes of index2 to be filtered out, one barcode per line.
--filter_by_index_threshold	integer	The allowed difference of index barcode for index filtering, default 0 means completely identical.

Name

Type & Properties

--filter_by_index1

file

--filter_by_index2

file

--filter_by_index_threshold

integer

Overlapped region correction

Name	Type & Properties	Description
--correction -c	boolean_true	Enable base correction in overlapped regions (only for PE data), default is disabled.
--overlap_len_require	integer	The minimum length to detect overlapped region of PE reads. This will affect overlap analysis based PE merge, adapter trimming and correction. 30 by default.
--overlap_diff_limit	integer	The maximum number of mismatched bases to detect overlapped region of PE reads. This will affect overlap analysis based PE merge, adapter trimming and correction. 5 by default.
--overlap_diff_percent_limit	integer	The maximum percentage of mismatched bases to detect overlapped region of PE reads. This will affect overlap analysis based PE merge, adapter trimming and correction. Default 20 means 20%.

Name

Type & Properties

--correction

-c

boolean_true

--overlap_len_require

integer

--overlap_diff_limit

integer

--overlap_diff_percent_limit

integer

UMI arguments

Name	Type & Properties	Description
--umi -U	boolean_true	Enable unique molecular identifier (UMI) preprocessing.
--umi_loc	string	Specify the location of UMI, can be (index1/index2/read1/read2/per_index/per_read, default is none.
--umi_len	integer	If the UMI is in read1/read2, its length should be provided.
--umi_prefix	string	If specified, an underline will be used to connect prefix and UMI (i.e. prefix=UMI, UMI=AATTCG, final=UMI_AATTCG). No prefix by default.
--umi_skip	integer	If the UMI is in read1/read2, fastp can skip several bases following UMI, default is 0.
--umi_delim	string	If the UMI is in index1/index2, fastp can use a delimiter to separate UMI from the read sequence, default is none.

Name

Type & Properties

--umi

-U

boolean_true

--umi_loc

string

--umi_len

integer

--umi_prefix

string

--umi_skip

integer

--umi_delim

string

Overrepresentation analysis arguments

Name	Type & Properties	Description
--overrepresentation_analysis -p	boolean_true	Enable overrepresentation analysis.
--overrepresentation_sampling	integer	One in (--overrepresentation_sampling) reads will be computed for overrepresentation analysis (1~10000), smaller is slower, default is 20.

Name

Type & Properties

--overrepresentation_analysis

-p

boolean_true

--overrepresentation_sampling

integer

Run this component

Run the following command to execute this component with Nextflow:

cat > params.yaml <<'EOM'  
out1: "$id.$key.out1.gz"  
out2: "$id.$key.out2.gz"  
unpaired1: "$id.$key.unpaired1.gz"  
unpaired2: "$id.$key.unpaired2.gz"  
failed_out: "$id.$key.failed_out.gz"  
overlapped_out: "$id.$key.overlapped_out"  
json: "$id.$key.json.json"  
html: "$id.$key.html.html"  
merged_out: "$id.$key.merged_out.gz"  
id: "run"  
publish_dir: "output/"  
EOM

nextflow run https://packages.viash-hub.com/vsh/biobox.git \  
  -revision v0.3.0 \  
  -main-script target/nextflow/fastp/main.nf \  
  -params-file params.yaml

fastp

Inputs

Outputs

Report output arguments

Adapter trimming

Base trimming

Merging mode

Additional input arguments

Additional output arguments

Logging arguments

Processing arguments

Deduplication arguments

PolyG tail trimming arguments

PolyX tail trimming arguments

Cut arguments

Quality filtering arguments

Length filtering arguments

Low complexity filtering arguments

Index filtering arguments

Overlapped region correction

UMI arguments

Overrepresentation analysis arguments

Run this component

Relationships

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Uses