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BP_UNFLATTEN_SEQ(1p) User Contributed Perl Documentation BP_UNFLATTEN_SEQ(1p)


bp_unflatten_seq - unflatten a genbank or genbank-style feature file into a nested SeqFeature hierarchy


  bp_unflatten_seq.PLS -e 3 -gff ~/cvs/bioperl-live/t/data/
  bp_unflatten_seq.PLS --detail ~/cvs/bioperl-live/t/data/
  bp_unflatten_seq.PLS -i foo.embl --from embl --to chadoxml -o out.chado.xml
  bp_unflatten_seq.PLS --notypemap --detail --to asciitree -ethresh 2


This script will unflatten a genbank or genbank-style file of SeqFeatures into a nested hierarchy.

See Bio::SeqFeature::Tools::Unflattener

In a GenBank/EMBL representation, features are 'flat' - for example, there is no link between an mRNA and a CDS, other than implicit links (eg via tags or via splice site coordinates) which may be hard to code for.

This is most easily illustrated with the default output format, asciitree

An unflattened genbank feature set may look like this (AB077698)

  Seq: AB077698
    databank_entry                                   1..2701[+]
        CDS hCHCR-G                                  80..1144[+]
        exon                                         80..1144[+]
      five_prime_UTR                                 1..79[+]
      located_sequence_feature                       137..196[+]
      located_sequence_feature                       239..292[+]
      located_sequence_feature                       617..676[+]
      located_sequence_feature                       725..778[+]
      three_prime_UTR                                1145..2659[+]
      polyA_site                                     1606..1606[+]
      polyA_site                                     2660..2660[+]

Or like this (portion of AE003734)

    mRNA CG3320-RA                                 
      CDS CG3320-PA                                53126..54971[-]
      exon                                         52204..53323[-]
      exon                                         53404..53631[-]
      exon                                         53688..53735[-]
      exon                                         53798..53918[-]
      exon                                         54949..55287[-]
    mRNA CG3320-RB                                 
      CDS CG3320-PB                                53383..54971[-]
      exon                                         52204..53631[-]
      exon                                         53688..53735[-]
      exon                                         53798..53918[-]
      exon                                         54949..55287[-]

The unflattening will also 'normalize' the containment hierarchy (in the sense of standardising it - e.g. making sure there is always a transcript record, even if genbank just specifies CDS and gene)

By default, the GenBank types will be mapped to SO types

See Bio::SeqFeature::Tools::TypeMapper


input file (can also be specified as last argument)
input format (defaults to genbank)

probably doesn't make so much sense to use this for non-flat formats; ie other than embl/genbank

output format (defaults to asciitree)

should really be a format that is nested SeqFeature aware; I think this is only asciitree, chadoxml and gff3

with export to GFF3 format (pre-3 GFFs make no sense with unflattened sequences, as they have no set way of representing feature graphs)
outfile defaults to STDOUT
show extra detail on features (asciitree mode only)
sets the error threshold on unflattening

by default this script will throw a wobbly if it encounters weird stuff in the genbank file - raise the error threshold to signal these to be ignored (and reported on STDERR)

suppress use_magic in unflattening (see Bio::SeqFeature::Tools::Unflattener
suppress type mapping (see Bio::SeqFeature::Tools::TypeMapper


Bio::SeqFeature::Tools::Unflattener allows fine-grained control over the unflattening process - need to add more options to allow this control at the command line


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 Chris Mungall E<lt>cjm-at-bioperl.orgE<gt>
2020-10-28 perl v5.30.3