The karyotype file defines the length and, if available, banding
pattern for all ideograms.

http://circos.ca/documentation/tutorials/ideograms/karyotypes/

For non-genomics applications, this file will contain a list of
segments (e.g. database tables, people, records, etc). The 'karyotype'
and 'chromosome' terminology should be interpreted as 'segment set'
and 'segment'.

################################################################

To create Circos karyotype files from UCSC Genome Browser tables (either
Assembly or Chromosome Band), use the parse.karyotype or assembly/parse.assembly scripts.