1. Circular sequences

Problem: Aside from GenBank format, virtually none of the common file formats has a mechanism to designate whether a DNA/RNA sequence is circular or linear. 

Workarounds:

• Reading files: Read the sequence in using File --> Open, NOT Import Foreign Format.
• Changing topology: Edit --> GetInfo. Set topology to Circular or Linear. Click on "Update".
  
• Use File --> Export Foreign format to export to a format that explicitly allows for specification of a circular topology. Only GenBank or EMBL formats have the ability to specify topology.
  

Problem: A pseudo-GenBank file is generated, omitting mostof the data normally in a GenBank file, and getting several of the lines in the wrong order.

Workaround: If you need to create a true GenBank file, use SEQUIN.

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