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Coronavirus annotation

Eric Nawrocki edited this page Apr 9, 2021 · 51 revisions

How to annotate SARS-CoV-2 sequences with VADR v1.2:

  1. Download and install the latest version of VADR, following the instructions on this page

  2. Download the latest coronavirus vadr models (gzipped tarball) from this FTP page, unpack them (e.g. tar xfz <tarball.gz>). Note the path to the directory name created (<sarscov2-models-dir-path>) for step 3.

  3. Run the v-annotate.pl program on an input fasta file with SARS-CoV-2 sequences using the recommended command and options below (the command is long so you will likely have to scroll to the right to view the entire command).

    NOTE: With 1.2 SARS-CoV-2 annotation using VADR now requires 2Gb of RAM per thread, down from 64Gb RAM. This command runs multithreaded on 8 CPUs, and so is only recommended if you have 8 CPUs and 16Gb RAM available. To run on <n> CPUs instead, replace --cpu 8 with --cpu <n>. To run single threaded on a single CPU remove the --cpu 8 option.

v-annotate.pl --cpu 8 --split -s -r --nomisc --mkey sarscov2 --lowsim5term 2 --lowsim3term 2 --fstlowthr 0.0 --alt_fail lowscore,fsthicnf,fstlocnf,insertnn,deletinn --mdir <sarscov2-models-dir-path> <fasta-file-to-annotate> <output-directory-to-create>

SARS-CoV-2 VADR models

As of April 13, 2021, the VADR model library used by GenBank for SARS-CoV-2 annotation (vadr-models-corona-1.2-2 model library) includes four SARS-CoV-2 models: NC_045512, NC_045512-del28254, NC045512-MW422255 (B.1.1.7), and NC_045512-MW809059 (B.1.525). You can determine which model was used to annotate any given input sequence in the .sqa vadr output files described more here.

The NC_045512 model has a length of 29903 nt and is based on the RefSeq NC_045512.2 sequence.

The NC_045512-del28254 model is identical to the NC_045512 model except that the single nucleotide at position 28254 is deleted. This single nucleotide deletion affects the stop codon for the ORF8 CDS relative to the NC_045512 RefSeq, extending the length of ORF8 by four amino acids in the NC_045512-del28254 model relative to the NC_045512 RefSeq model.

The NC_045512-MW422255 model has a length of 29884 nt and is based on the MW422255.1 sequence but modified as follows:

  • extending the MW422255 sequence by 54 nt on the 5' end and 67 nt on the 3' end so the 5' and 3' ends match up with the NC_045512 RefSeq sequence, using the nucleotides from NC_045512

  • replacing the 8 N nucleotides with the corresponding nucleotide from NC_045512

The addition of NC_045512-MW422255 is aimed at facilitating submission of sequences from lineages currently referred to as B.1.1.7, 501Y.V1 or 20I.

The NC_045512-MW809059 model has a length of 29830 nt and is based on the MW809059.1 sequence but modified as follows:

  • extending the MW809059 sequence by 2 nt on the 5' end and 50 nt on the 3' end so the 5' and 3' ends match up with the NC_045512 RefSeq sequence, using the nucleotides from NC_045512

The addition of NC_045512-MW422255 is aimed at facilitating submission of sequences from the lineage currently referred to as B.1.525.

The following table includes information on the 12 CDS features in the NC_045512 RefSeq and the two variant models:

CDS product gene NC_045512 model positions NC_045512-MW422255 model positions NC_045512-MW809059 model positions
ORF1ab polyprotein ORF1ab 266-13468,13468-21555 266-13459,13459-21546 266-13459,13459-21546
ORF1a polyprotein ORF1ab 266-13483 266-13474 266-13474
surface glycoprotein S 21563-25384 21554-25366 21554-25366
ORF3a protein ORF3a 25393-26220 25375-26202 25375-26202
envelope protein E 26245-26472 26227-26454 26227-26454
membrane glycoprotein M 26523-27191 26505-27173 26505-27173
ORF6 protein ORF6 27202-27387 27184-27369 27184-27366
ORF7a protein ORF7a 27394-27759 27376-27741 27373-27738
ORF7b ORF7b 27756-27887 27738-27869 27735-27866
ORF8 protein ORF8 27894-28259 27876-27956 27873-28238
nucleocapsid phosphoprotein N 28274-29533 28255-29514 28253-29509
ORF10 protein ORF10 29558-29674 29539-29655 29534-29650

The ORF8 protein CDS is italicized above because it is 285nt (95aa) shorter in the NC_045512-MW422255 model due to an earlier stop codon and it is annotated as truncated ORF8 protein in the output VADR feature table file in sequences classified to the NC_045512-MW422255 model.

This section shows output from an example v-annotate.pl annotation of three SARS-CoV-2 sequences from GenBank using the same command and options that GenBank currently uses to screen incoming SARS-CoV-2 sequences.

The fasta file of those three sequences can be downloaded here.

(A similar example for norovirus sequences, which may contain more details on certain aspects, is here.)

For this example, the coronavirus model directory is in /usr/local/vadr-models-corona-1.2-2 and the sars-cov2.3.fa sequence file is in the current directory, and we will create a new directory called my3 into which output files will be written.

To annotate these sequences using the recommended v-annotate.pl options for SARS-CoV-2, run the command (scroll to right to see full command):

v-annotate.pl --cpu 8 --split -s -r --nomisc --mkey sarscov2 --lowsim5term 2 --lowsim3term 2 --fstlowthr 0.0 --alt_fail lowscore,fsthicnf,fstlocnf,insertnn,deletinn --mdir /usr/local/vadr-models-corona-1.1.3-1 sars-cov2.3.fa my3

The options used are explained further below.

When you execute the above command, you should see output similar to the following block that lists relevant environment variable values, and input arguments and options:

# v-annotate.pl :: classify and annotate sequences using a CM library
# VADR 1.2 (April 2021)
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# date:              Fri Apr  9 16:19:15 2021
# $VADRBIOEASELDIR:  /panfs/pan1/infernal/notebook/21_0223_vadr_1p2_release/test-installs/vadr-install-dir/Bio-Easel
# $VADRBLASTDIR:     /panfs/pan1/infernal/notebook/21_0223_vadr_1p2_release/test-installs/vadr-install-dir/ncbi-blast/bin
# $VADREASELDIR:     /panfs/pan1/infernal/notebook/21_0223_vadr_1p2_release/test-installs/vadr-install-dir/infernal/binaries
# $VADRINFERNALDIR:  /panfs/pan1/infernal/notebook/21_0223_vadr_1p2_release/test-installs/vadr-install-dir/infernal/binaries
# $VADRMODELDIR:     /panfs/pan1/infernal/notebook/21_0223_vadr_1p2_release/test-installs/vadr-install-dir/vadr-models-calici
# $VADRSCRIPTSDIR:   /panfs/pan1/infernal/notebook/21_0223_vadr_1p2_release/test-installs/vadr-install-dir/vadr
#
# sequence file:                                                                       sars-cov2.3.fa
# output directory:                                                                    my3
# specify that alert codes in <s> cause FAILure:                                       lowscore,fsthicnf,fstlocnf,insertnn,deletinn [--alt_fail]
# .cm, .minfo, blastn .fa files in $VADRMODELDIR start with key <s>, not 'vadr':       sarscov2 [--mkey]
# model files are in directory <s>, not in $VADRMODELDIR:                              /panfs/pan1/dnaorg/virseqannot/code/vadr-models-sarscov2-1.2-2dev2 [--mdir]
# in feature table for failed seqs, never change feature type to misc_feature:         yes [--nomisc]
# lowsim5{s,f}/LOW_{FEATURE_}SIMILARITY_START minimum length is <n>:                   2 [--lowsim5term]
# lowsim3{s,f}/LOW_{FEATURE_}SIMILARITY_END minimum length is <n>:                     2 [--lowsim3term]
# fstlocnf/POSSIBLE_FRAMESHIFT_LOW_CONF minimum average probability for alert is <x>:  0.0 [--fstlowthr]
# use max length ungapped region from blastn to seed the alignment:                    yes [-s]
# replace stretches of Ns with expected nts, where possible:                           yes [-r]
# split input file into chunks, run each chunk separately:                             yes [--split]
# parallelize across <n> CPU workers (requires --split or --glsearch):                 8 [--cpu]
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Next, v-annotate.pl will output information as it proceeds through different steps of the analysis:

# Validating input                                                                        ... done. [    0.3 seconds]
# Splitting sequence file into chunks to run independently in parallel on 8 processors    ... done. [    0.0 seconds]
# Executing 1 script to process 1 partition(s) of all 3 sequence(s)                       ... done. [   13.1 seconds]
# Merging and finalizing output                                                           ... done. [    1.1 seconds]

With the --split --cpu 8 options, the input fasta script is split up into chunks of about 10 full length SARS-CoV-2 each and runs v-annotate.pl separately on those chunks on 8 different CPUs in parallel. When all sequences are finished processing the main script merges the output together. In this example, there are only 3 sequences so there is only 1 chunk run on 1 CPU, but with larger input sequence files, there will be more chunks run in parallel.

The v-annotate.pl output then includes a summary of the classification of sequences, and the alerts reported:

# Summary of classified sequences:
#
#                                           num   num   num
#idx  model      group         subgroup    seqs  pass  fail
#---  ---------  ------------  ----------  ----  ----  ----
1     NC_045512  Sarbecovirus  SARS-CoV-2     3     2     1
#---  ---------  ------------  ----------  ----  ----  ----
-     *all*      -             -              3     2     1
-     *none*     -             -              0     0     0
#---  ---------  ------------  ----------  ----  ----  ----
#
# Summary of reported alerts:
#
#     alert     causes   short                            per    num   num  long
#idx  code      failure  description                     type  cases  seqs  description
#---  --------  -------  ---------------------------  -------  -----  ----  -----------
1     cdsstopn  yes*     CDS_HAS_STOP_CODON           feature      2     1  in-frame stop codon exists 5' of stop position predicted by homology to reference
2     cdsstopp  yes*     CDS_HAS_STOP_CODON           feature      2     1  stop codon in protein-based alignment
3     peptrans  yes*     PEPTIDE_TRANSLATION_PROBLEM  feature     26     1  mat_peptide may not be translated because its parent CDS has a problem
#---  --------  -------  ---------------------------  -------  -----  ----  -----------

And finally a long list of the output files created (truncated for brevity):

# Output printed to screen saved in:                              my3.vadr.log
# List of executed commands saved in:                             my3.vadr.cmd
# List and description of all output files saved in:              my3.vadr.filelist
# esl-seqstat -a output for input fasta file saved in:            my3.vadr.seqstat
# 5 column feature table output for passing sequences saved in:   my3.vadr.pass.tbl
# 5 column feature table output for failing sequences saved in:   my3.vadr.fail.tbl
# list of passing sequences saved in:                             my3.vadr.pass.list
# list of failing sequences saved in:                             my3.vadr.fail.list
# list of alerts in the feature tables saved in:                  my3.vadr.alt.list
# fasta file with passing sequences saved in:                     my3.vadr.pass.fa
# fasta file with failing sequences saved in:                     my3.vadr.fail.fa
# per-sequence tabular annotation summary file saved in:          my3.vadr.sqa
# per-sequence tabular classification summary file saved in:      my3.vadr.sqc
# per-feature tabular summary file saved in:                      my3.vadr.ftr
# per-model-segment tabular summary file saved in:                my3.vadr.sgm
# per-model tabular summary file saved in:                        my3.vadr.mdl
# per-alert tabular summary file saved in:                        my3.vadr.alt
# alert count tabular summary file saved in:                      my3.vadr.alc
# alignment doctoring tabular summary file saved in:              my3.vadr.dcr
# ungapped seed alignment summary file (-s) saved in:             my3.vadr.sda
# replaced stretches of Ns summary file (-r) saved in:            my3.vadr.rpn
#
# All output files created in directory ./my3/
#
# Elapsed time:  00:00:14.73
#                hh:mm:ss
# 
[ok]

Note that all the output files will be in the newly created my3 directory. The Summary of classified sequences listed that two sequences passed and one failed. The file my3.vadr.pass.list, lists the two sequences that passed:

MT159720.1
MT308693.1

and my3.vadr.fail.list lists the one sequence that failed:

MT159720.1/1406-G-to-T

Also, FASTA-formatted sequence files for each the passing and failing sequences are my3.vadr.pass.fa and my3.vadr.fail.fa.

For the two sequences that passed, the annotation is available in the output my3.vadr.pass.tbl file and for the sequence that failed the annotation is in the my3.vadr.fail.tbl file.

my.vadr.pass.tbl: (with the middle of the table for each sequence removed for brevity)

>Feature MT159720.1
266	21555	gene
			gene	ORF1ab
266	13468	CDS
13468	21555
			product	ORF1ab polyprotein
			exception	ribosomal slippage
			protein_id	MT159720.1_1
266	13483	CDS
			product	ORF1a polyprotein
			protein_id	MT159720.1_2
266	805	mat_peptide
			product	leader protein
			protein_id	MT159720.1_1

...snip...

28274	29533	gene
			gene	N
28274	29533	CDS
			product	nucleocapsid phosphoprotein
			protein_id	MT159720.1_11
29558	29674	gene
			gene	ORF10
29558	29674	CDS
			product	ORF10 protein
			protein_id	MT159720.1_12
29609	29644	stem_loop
			note	Coronavirus 3' UTR pseudoknot stem-loop 1
29629	29657	stem_loop
			note	Coronavirus 3' UTR pseudoknot stem-loop 2
29728	29768	stem_loop
			note	Coronavirus 3' stem-loop II-like motif (s2m)
>Feature MT308693.1
217	21506	gene
			gene	ORF1ab
217	13419	CDS
13419	21506
			product	ORF1ab polyprotein
			exception	ribosomal slippage
			protein_id	MT308693.1_1
217	13434	CDS
			product	ORF1a polyprotein
			protein_id	MT308693.1_2
217	756	mat_peptide
			product	leader protein
			protein_id	MT308693.1_1

...snip...

28225	29484	gene
			gene	N
28225	29484	CDS
			product	nucleocapsid phosphoprotein
			protein_id	MT308693.1_11
29509	29625	gene
			gene	ORF10
29509	29625	CDS
			product	ORF10 protein
			protein_id	MT308693.1_12
29560	29595	stem_loop
			note	Coronavirus 3' UTR pseudoknot stem-loop 1
29580	29608	stem_loop
			note	Coronavirus 3' UTR pseudoknot stem-loop 2
29679	29719	stem_loop
			note	Coronavirus 3' stem-loop II-like motif (s2m)

my.vadr.fail.tbl (with the middle removed for brevity):

>Feature MT159720.1/1406-G-to-T
266	21555	gene
			gene	ORF1ab
266	13468	CDS
13468	21555
			product	ORF1ab polyprotein
			exception	ribosomal slippage
			protein_id	MT159720.1/1406-G-to-T_1
266	13483	CDS
			product	ORF1a polyprotein
			protein_id	MT159720.1/1406-G-to-T_2
266	805	mat_peptide
			product	leader protein
			protein_id	MT159720.1/1406-G-to-T_1

...snip...

29629	29657	stem_loop
			note	Coronavirus 3' UTR pseudoknot stem-loop 2
29728	29768	stem_loop
			note	Coronavirus 3' stem-loop II-like motif (s2m)

Additional note(s) to submitter:
ERROR: CDS_HAS_STOP_CODON: (ORF1ab polyprotein) in-frame stop codon exists 5' of stop position predicted by homology to reference [revised to 266..1408 (stop shifted 20147 nt)]
ERROR: CDS_HAS_STOP_CODON: (ORF1ab polyprotein) stop codon in protein-based alignment [stop codon(s) end at position(s) 1143]
ERROR: CDS_HAS_STOP_CODON: (ORF1a polyprotein) in-frame stop codon exists 5' of stop position predicted by homology to reference [revised to 266..1408 (stop shifted 12075 nt)]
ERROR: CDS_HAS_STOP_CODON: (ORF1a polyprotein) stop codon in protein-based alignment [stop codon(s) end at position(s) 1408]
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (leader protein) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (nsp2) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (nsp3) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (nsp4) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (3C-like proteinase) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (nsp6) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (nsp7) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (nsp8) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (nsp9) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (nsp10) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (RNA-dependent RNA polymerase) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (helicase) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (3'-to-5' exonuclease) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (endoRNAse) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (2'-O-ribose methyltransferase) mat_peptide may not be translated because its parent CDS has a problem
ERROR: PEPTIDE_TRANSLATION_PROBLEM: (nsp11) mat_peptide may not be translated because its parent CDS has a problem

Feature table format is described at https://www.ncbi.nlm.nih.gov/Sequin/table.html.

Note that the end of the fail.tbl file lists ERRORs for MT159720.1/1406-G-to-T, the third sequence in the input file, which is identical to the first one MT159720.1 with position 1406 changed from a G to a T to purposefully introduce an early stop codon for purposes of this example. Early stop codons are one reason a sequence can fail. Note the CDS_HAS_STOP_CODON errors at the end of the feature table. The PEPTIDE_TRANSLATION_PROBLEM occur for the mature peptide features which are derived from the two CDS that have errors.

The annotation information is also available in other files with different formats, such as the my3/my3.vadr.ftr file, which may be easier to parse for some applications. For more information on how to interpret these results and files, including file formats, see the vadr documentation pages, linked to from here, or the VADR 1.0 paper (reference below).

HERE HERE HERE

Explanation of options used in example command

The options used in the above command are the recommended set of options for SARS-CoV-2 annotation because they are currently (as of Jan 5, 2021) being used by NCBI sequence indexers when they evaluate an incoming SARS-CoV-2 sequence submission. The options are each briefly explained in the table below. More information can be found here, and the -s and -r options are explained more below the table as well.

option explanation
--mxsize 64000 set the maximum allowed dynamic programming matrix size for the cmalign program to 64Gb
-s turn on the seed acceleration heuristic: use the max length ungapped region from blastn to seed the alignment
-r turn on the replace-N strategy: replace stretches of Ns with expected nucleotides, where possible
--nomisc specify that features for failing sequences not be changed to misc_features in the output .tbl file
--lowsim5term 2 set the minimum length for an alert related to sequence of low similarity to the RefSeq at the 5' sequence end to 2 nt
--lowsim3term 2 set the minimum length for an alert related to sequence of low similarity to the RefSeq at the 3' sequence end to 2 nt
--mkey NC_045512 use the model files with prefix NC_045512 in the directory from --mdir
--mdir /usr/local/vadr-models-corona-1.1-1 specify that the models to use are in directory /usr/local/vadr-models-corona-1.1-2
--fstlowthr 0.0 specify that all possible frameshifts are reported as alerts (minimum average posterior probability of 0.0)
--alt_fail lowscore,fsthicnf,fstlocnf,insertnn,deletinn specify that lowscore, frameshirt alerts (fsthicnf,fstlocnf) and large insertions and deletions (insertnn,deletinn) cause a sequence to fail

The -r option

The -r option replaces stretches of Ns in the input sequences with the expected nucleotides from the RefSeq. Be cautious, as this strategy actually replaces Ns in your sequence prior to determination of annotation. If this is not what you want to do, then do not use -r. Using -r is the current (as of May 7, 2020) practice for NCBI indexers analyzing incoming SARS-CoV-2 sequences, which is why it is included as a recommended option here. By doing this the Ns are assumed to be the 'expected' sequence in the corresponding regions for purposes of annotation. More information on -r, including information on other related options is here.

The second sequence in the sars-cov2.3.fa file includes 344 Ns, most of which are contained within consecutive stretches of 36 and 290 Ns in two regions, from sequence positions 11487-11522 and 19237-19526. With the -r option, v-annotate.pl replaces the Ns in these two stretches with the corresponding 'expected' nucleotides from the NC_045512 RefSeq, and then determines annotation with that doctored sequence. Some information on the Ns in each sequence including on those that were replaced is output to a file with suffix .rpn (format described here). For the example above, the my3.vadr.rpn file looks like this (scroll to right to see full file):

#seq  seq                       seq                   num_Ns  num_Ns  fract_Ns  ngaps  ngaps  ngaps    ngaps    ngaps      nnt      nnt  replaced_coords      
#idx  name                      len  model      p/f      tot      rp        rp    tot    int     rp  rp-full  rp-part  rp-full  rp-part  seq(S),mdl(M),#rp(N);
#---  ----------------------  -----  ---------  ----  ------  ------  --------  -----  -----  -----  -------  -------  -------  -------  ---------------------
1     MT159720.1              29882  NC_045512  PASS       0       0         -      0      0      0        0        0        0        0  -                    
2     MT308693.1              29788  NC_045512  PASS     344     326     0.948      2      2      2        2        0      326        0  S:11487..11522,M:11536..11571,N:36/36;S:19237..19526,M:19286..19575,N:290/290;
3     MT159720.1/1406-G-to-T  29882  NC_045512  FAIL       0       0         -      0      0      0        0        0        0        0  -                    

If we run the above command without -r, the Ns are not replaced and the MT308693.1 sequence fails because the N regions trigger alerts/errors to be reported. Specifically, the following three errors are reported in the fail.tbl file, amongst other PEPTIDE_TRANSLATION_PROBLEM errors for mature peptides (not shown):

ERROR: LOW_FEATURE_SIMILARITY: (ORF1ab) region within annotated feature lacks significant similarity [36 nt overlap b/t low similarity region (11487..11522) and annotated feature (217..21506), strand: +]
ERROR: LOW_FEATURE_SIMILARITY: (ORF1ab) region within annotated feature lacks significant similarity [290 nt overlap b/t low similarity region (19237..19526) and annotated feature (217..21506), strand: +]
ERROR: INDEFINITE_ANNOTATION_END: (ORF1ab polyprotein) protein-based alignment does not extend close enough to nucleotide-based alignment 3' endpoint [2271 > 8 (strand:+ CM:21506 blastx:21506 - 2271, valid stop codon in CM prediction)]

Note that the regions that are causing the LOW_FEATURE_SIMILARITY errors are stretches of Ns. Using -r allows some sequences like this that only fail due to the Ns to pass, and sometimes changes their annotation to be more accurate (based on the assumption that the replaced Ns represent the expected nucleotides at the corresponding positions).

The -s option

The -s option speeds up v-annotate.pl by identifying the maximum length ungapped alignment region using blastn, and fixing that part of the alignment to accelerate the usually much slower cmalign alignment step. This heuristic works particularly well for many SARS-CoV-2 sequences that are highly similar (~99% identical) to the RefSeq NC_045512. If we run the above example command without -s, it would require several minutes per sequence instead of several seconds per sequence. When -s is used, an additional output file with suffix .sda is output (format described here). More information on -s, including information on other related options is here.

The command above will only compare your input sequences to the three models described above (NC_045512, NC_045512-del28254 and NC_045512-MW422255). If you want to annotate v-annotate.pl to perform the additional step of checking if each input sequence is more similar to SARS-CoV-2 or a different Coronaviridae RefSeq, or if your input file contains non-SARS-CoV-2 Coronaviridae sequences, you can download a different model file that includes the NC_045512 RefSeq and 54 other Coronaviridae RefSeqs from this FTP page.

After downloading and unpacking that model set, change the --mkey option in the example command above from

--mkey NC_045512

to

--mkey corona

But be aware that changing this option will result in slower running times.

Note also that this is an older model file and it only includes the NC_045512 model, and not the other 2 models in the 1.1.3-1 set. (I decided to stop including the 54 other Coronaviridae models in the 1.1.3-1 set to make the file size of the model set smaller and more portable, but if you're interested in combining these two model sets, contact me.)

You can use VADR's v-build.pl program to build additional models of Coronaviridae GenBank sequences. More information is here.


Reference

  • The recommended citation for using VADR is: Alejandro A Schäffer, Eneida L Hatcher, Linda Yankie, Lara Shonkwiler, J Rodney Brister, Ilene Karsch-Mizrachi, Eric P Nawrocki; VADR: validation and annotation of virus sequence submissions to GenBank. BMC Bioinformatics 21, 211 (2020). https://doi.org/10.1186/s12859-020-3537-3

Questions, comments, feature or model requests? Send a mail to eric.nawrocki@nih.gov.