skip to navigation
skip to content

biopython 1.70

Freely available tools for computational molecular biology.

Biopython README file

The Biopython Project is an international association of developers of freely available Python tools for computational molecular biology.

Our user-centric documentation is hosted on including the main Biopython Tutorial and Cookbook:

This README file is intended primarily for people interested in working with the Biopython source code, either one of the releases from the website, or from our repository on GitHub

The NEWS file summarises the changes in each release of Biopython.

The Biopython package is open source software made available under generous terms. Please see the LICENSE file for further details.

If you use Biopython in work contributing to a scientific publication, we ask that you cite our application note (below) or one of the module specific publications (listed on our website):

Cock, P.J.A. et al. Biopython: freely available Python tools for computational molecular biology and bioinformatics. Bioinformatics 2009 Jun 1; 25(11) 1422-3 pmid:19304878

For the impatient

Windows users are currently recommended to use the installation packages provided on our website, – further instructions are given below.

Python 2.7.9 onwards, and Python 3.4 onwards, include the package management system “pip” which should allow you to install Biopython with just:

pip install numpy
pip install biopython

Otherwise you may have to build and install Biopython, which is described below.

Python Requirements

We currently recommend using Python 3.6 from

Biopython is currently supported and tested on the following Python implementations:

  • Python 2.7, 3.4, 3.5, 3.6 – see

    This is the primary development platform for Biopython.

  • PyPy v5.7 and also PyPy3.5 v5.8 beta – see

    Aside from Bio.trie (which does not compile as marshal.h is currently missing under PyPy), everything should work. Older versions of PyPy mostly work too.

  • Jython 2.7 – see

    We have decided to deprecate support for Jython, but aside from Bio.Restriction, modules with C code, or dependent on SQLite3 or NumPy, everything should work. There are some known issues with test failures which have not yet been resolved.

Biopython 1.68 was our final release to support Python 2.6.


The following are required at compile time - unless you are using Jython (support for which is deprecated) or IronPython (which we do not officially support):

  • NumPy, see This package is used in Bio.Cluster, Bio.PDB and a few other modules. We use the NumPy C API, which means it must be installed before compiling Biopython’s C code.

Optional Dependencies

Depending on which parts of Biopython you plan to use, there are a number of other optional Python dependencies, which can be installed later if needed:

Note that some of these libraries are not available for Jython or PyPy, and not all are available for Python 3 yet either.

In addition there are a number of useful third party tools you may wish to install such as standalone NCBI BLAST, EMBOSS or ClustalW.


First, make sure that Python is installed correctly. Second (except for Jython or IronPython), make sure NumPy is installed. Then install Biopython.

Windows users should use the appropriate provided installation package from our website (each is specific to a different Python version).

Python 2.7.9 onwards, and Python 3.4 onwards, include the package management system “pip” which should allow you to install Biopython with just:

pip install numpy
pip install biopython

Otherwise you may have to build and install Biopython which should be as going to the Biopython source code directory, and typing:

python build
python test
sudo python install

Substitute python with your specific version, for example python3, jython or pypy`.

If you need to do additional configuration, e.g. changing the base directory, please type python, or see the documentation here:


Biopython includes a suite of regression tests to check if everything is running correctly. To run the tests, go to the biopython source code directory and type:

python build
python test

Do not panic if you see messages warning of skipped tests:

test_DocSQL ... skipping. Install MySQLdb if you want to use Bio.DocSQL.

This most likely means that a package is not installed. You can ignore this if it occurs in the tests for a module that you were not planning on using. If you did want to use that module, please install the required dependency and re-run the tests.

Some of the tests may fail due to network issues, this is often down to chance or a service outage. If the problem does not go away on re-running the tests, it is possible to run only the offline tests.

There is more testing information in the Biopython Tutorial & Cookbook.

Experimental code

Biopython 1.61 introduced a new warning, Bio.BiopythonExperimentalWarning, which is used to mark any experimental code included in the otherwise stable Biopython releases. Such ‘beta’ level code is ready for wider testing, but still likely to change, and should only be tried by early adopters in order to give feedback via the biopython-dev mailing list.

We’d expect such experimental code to reach stable status within one or two releases, at which point our normal policies about trying to preserve backwards compatibility would apply.


While we try to ship a robust package, bugs inevitably pop up. If you are having problems that might be caused by a bug in Biopython, it is possible that it has already been identified. Update to the latest release if you are not using it already, and retry. If the problem persists, please search our bug database and our mailing lists to see if it has already been reported (and hopefully fixed), and if not please do report the bug. We can’t fix problems we don’t know about ;)

If you suspect the problem lies within a parser, it is likely that the data format has changed and broken the parsing code. (The text BLAST and GenBank formats seem to be particularly fragile.) Thus, the parsing code in Biopython is sometimes updated faster than we can build Biopython releases. You can get the most recent parser by pulling the relevant files (e.g. the ones in Bio.SeqIO or Bio.Blast) from our git repository. However, be careful when doing this, because the code in github is not as well-tested as released code, and may contain new dependencies.

Finally, you can send a bug report to the bug database or the mailing list at (subscription required). In the bug report, please let us know:

  1. Which operating system and hardware (32 bit or 64 bit) you are using
  2. Python version
  3. Biopython version (or git commit/date)
  4. Traceback that occurs (the full error message)

And also ideally:

  1. Example code that breaks
  2. A data file that causes the problem

Contributing, Bug Reports

Biopython is run by volunteers from all over the world, with many types of backgrounds. We are always looking for people interested in helping with code development, web-site management, documentation writing, technical administration, and whatever else comes up.

If you wish to contribute, please visit the web site and join our mailing list:

Distribution Structure

  • README.rst – This file.
  • NEWS.rst – Release notes and news.
  • LICENSE.rst – What you can do with the code.
  • CONTRIB.rst – An (incomplete) list of people who helped Biopython in one way or another.
  • DEPRECATED.rst – Contains information about modules in Biopython that are removed or no longer recommended for use, and how to update code that uses those modules.
  • – Configures which files to include in releases.
  • – Installation file.
  • Bio/ – The main code base code.
  • BioSQL/ – Code for using Biopython with BioSQL databases.
  • Doc/ – Documentation.
  • Scripts/ – Miscellaneous, possibly useful, standalone scripts.
  • Tests/ – Regression testing code including sample data files.
File Type Py Version Uploaded on Size
biopython-1.70-cp27-cp27m-macosx_10_6_intel.macosx_10_9_intel.macosx_10_9_x86_64.macosx_10_10_intel.macosx_10_10_x86_64.whl (md5) Python Wheel cp27 2017-07-18 1MB
biopython-1.70-cp27-cp27m-manylinux1_i686.whl (md5) Python Wheel cp27 2017-07-18 2MB
biopython-1.70-cp27-cp27m-manylinux1_x86_64.whl (md5) Python Wheel cp27 2017-07-18 2MB
biopython-1.70-cp27-cp27m-win32.whl (md5) Python Wheel cp27 2017-07-18 1MB
biopython-1.70-cp27-cp27m-win_amd64.whl (md5) Python Wheel cp27 2017-07-18 1MB
biopython-1.70-cp27-cp27mu-manylinux1_i686.whl (md5) Python Wheel cp27 2017-07-18 2MB
biopython-1.70-cp27-cp27mu-manylinux1_x86_64.whl (md5) Python Wheel cp27 2017-07-18 2MB
biopython-1.70-cp34-cp34m-macosx_10_6_intel.macosx_10_9_intel.macosx_10_9_x86_64.macosx_10_10_intel.macosx_10_10_x86_64.whl (md5) Python Wheel cp34 2017-07-18 1MB
biopython-1.70-cp34-cp34m-manylinux1_i686.whl (md5) Python Wheel cp34 2017-07-18 2MB
biopython-1.70-cp34-cp34m-manylinux1_x86_64.whl (md5) Python Wheel cp34 2017-07-18 2MB
biopython-1.70-cp34-cp34m-win32.whl (md5) Python Wheel cp34 2017-07-18 1MB
biopython-1.70-cp34-cp34m-win_amd64.whl (md5) Python Wheel cp34 2017-07-18 1MB
biopython-1.70-cp35-cp35m-macosx_10_6_intel.macosx_10_9_intel.macosx_10_9_x86_64.macosx_10_10_intel.macosx_10_10_x86_64.whl (md5) Python Wheel cp35 2017-07-18 1MB
biopython-1.70-cp35-cp35m-manylinux1_i686.whl (md5) Python Wheel cp35 2017-07-18 2MB
biopython-1.70-cp35-cp35m-manylinux1_x86_64.whl (md5) Python Wheel cp35 2017-07-18 2MB
biopython-1.70-cp35-cp35m-win32.whl (md5) Python Wheel cp35 2017-07-18 1MB
biopython-1.70-cp35-cp35m-win_amd64.whl (md5) Python Wheel cp35 2017-07-18 1MB
biopython-1.70-cp36-cp36m-macosx_10_6_intel.macosx_10_9_intel.macosx_10_9_x86_64.macosx_10_10_intel.macosx_10_10_x86_64.whl (md5) Python Wheel cp36 2017-07-18 1MB
biopython-1.70-cp36-cp36m-manylinux1_i686.whl (md5) Python Wheel cp36 2017-07-18 2MB
biopython-1.70-cp36-cp36m-manylinux1_x86_64.whl (md5) Python Wheel cp36 2017-07-18 2MB
biopython-1.70-cp36-cp36m-win32.whl (md5) Python Wheel cp36 2017-07-18 1MB
biopython-1.70-cp36-cp36m-win_amd64.whl (md5) Python Wheel cp36 2017-07-18 1MB
biopython-1.70.tar.gz (md5) Source 2017-07-11 14MB