Python package for annotating gene features
- Free software: LGPL 3.0
- Documentation: https://seqann.readthedocs.io.
- Jupyter Notebook
The seqann
package allows
users to annotate gene features in consensus sequences. Annotations can be created by passing consensus sequences to the annotate
method in the
BioSeqAnn
class. No parameters are required when initalizing a BioSeqAnn
class. However, annotations can be
created significantly faster when using a BioSQL database. When a BioSQL database is not provided the lastest hla.dat file is downloaded and parsed.
A BioSQL database containing all of IPD-IMGT/HLA is available on DockerHub and can be
run on any machine that has docker installed.
Below are the list of parameters and the default values used when initalizing a BioSeqAnn
object.
Parameter | Type | Default | Description |
---|---|---|---|
server | BioSeqDatabase |
None | A BioSQL database containing all of the sequence data from IPD-IMGT/HLA. |
dbversion | str |
Latest | The IPD-IMGT/HLA or KIR database release. |
datfile | str |
None | The IPD-IMGT/HLA or KIR dat file to use in place of the server parameter. |
kir | bool |
False | Flag for indicating the input sequences are from the KIR gene system. |
align | bool |
False | Flag for producing the alignments along with the annotations. |
verbose | bool |
False | Flag for running in verbose mode. |
verbosity | int |
None | Numerical value to indicate how verbose the output will be in verbose mode. |
debug | Dict |
None | A dictionary containing a process names as the key and verbosity as the value |
To annotated a sequence initialize a new BioSeqAnn
object and then pass the sequence to the
annotate
method. The sequence must be a Biopython Seq
. The locus of the sequence is not required but it will improve the accuracy of the annotation.
from seqann import BioSeqAnn
seqann = BioSeqAnn()
ann = seqann.annotate(sequence, "HLA-A")
The annotation of sequence can be done with or without providing a BioSeqDatabase
. To use a BioSQL database
initialize a BioSeqDatabase
with the parameters that match the database you have running. If you are
running the imgt_biosqldb from DockerHub then the following parameters we be the same.
from seqann import BioSeqAnn
from BioSQL import BioSeqDatabase
server = BioSeqDatabase.open_database(driver="pymysql", user="root",
passwd="my-secret-pw", host="localhost",
db="bioseqdb", port=3306)
seqann = BioSeqAnn(server=server)
ann = seqann.annotate(sequence, "HLA-A")
{
'complete_annotation': True,
'annotation': {'exon_1': SeqRecord(seq=Seq('AGAGACTCTCCCG', SingleLetterAlphabet()), id='HLA:HLA00630', name='HLA:HLA00630', description='HLA:HLA00630 DQB1*03:04:01 597 bp', dbxrefs=[]),
'exon_2': SeqRecord(seq=Seq('AGGATTTCGTGTACCAGTTTAAGGCCATGTGCTACTTCACCAACGGGACGGAGC...GAG', SingleLetterAlphabet()), id='HLA:HLA00630', name='HLA:HLA00630', description='HLA:HLA00630 DQB1*03:04:01 597 bp', dbxrefs=[]),
'exon_3': SeqRecord(seq=Seq('TGGAGCCCACAGTGACCATCTCCCCATCCAGGACAGAGGCCCTCAACCACCACA...ATG', SingleLetterAlphabet()), id='HLA:HLA00630', name='<unknown name>', description='HLA:HLA00630', dbxrefs=[])},
'features': {'exon_1': SeqFeature(FeatureLocation(ExactPosition(0), ExactPosition(13), strand=1), type='exon_1'),
'exon_2': SeqFeature(FeatureLocation(ExactPosition(13), ExactPosition(283), strand=1), type='exon_2')
'exon_3': SeqFeature(FeatureLocation(ExactPosition(283), ExactPosition(503), strand=1), type='exon_3')},
'method': 'nt_search and clustalo',
'gfe': 'HLA-Aw2-1-1-1-1-1-1-1-1-1-1-1-1-1-1-1-4',
'seq': SeqRecord(seq=Seq('AGAGACTCTCCCGAGGATTTCGTGTACCAGTTTAAGGCCATGTGCTACTTCACC...ATG', SingleLetterAlphabet()), id='HLA:HLA00630', name='HLA:HLA00630', description='HLA:HLA00630 DQB1*03:04:01 597 bp', dbxrefs=[])
}
Once a sequence has been annotated the gene features and their corresponding sequences are available in the returned Annotation
object. If a full
annotation is not able to be produced then nothing will be returned. Below is an example showing how the features can be accessed and printed out.
ann = seqann.annotate(sequence, "HLA-A")
for feat in ann.annotation:
print(feat, ann.gfe, str(ann.annotation[feat].seq), sep="\t")
pip install seqann
- Clustal Omega 1.2.0 or higher
- Python 3.6
- blastn