• Returns ortholog of gene-or-protein in given organism or set of organisms
• If IN organism is not specified, then returns orthologs in all available organisms
• "Ortholog" is defined as Two-way-ortholog-of, where protein A in organism X is the best blast hit of protein B in organism Y and vice versa, both hits better than a cutoff E-value
• Only one ortholog is returned for a gene or protein. If you want all similar genes or proteins, as defined by E-value or mismatches, use PROTEINS-SIMILAR-TO or GENES-SIMILAR-TO
• Entity may be:
  • A single gene or protein
    • Frame name (e.g. #$A7120.all4312)
    • Name in string (e.g. ''A7120.all4312'')
    • Short name (e.g. all4312)
    • Symbol of name or short name (e.g. 'all4312)
    • Variable holding name or short name
  • A replicon or contiguous sequence (same formats as above)
  • An organism
    • Any legitimate nickname of organism
  • A list of any of the above (may be mixed)
• If entity is a gene, then the ortholog in the given organism is returned as a gene
• If entity is a protein, then the ortholog in the given organism is returned as a protein
• If entity is a contig or replicon, then a list is returned consisting of orthologs in the given organism of all proteins in the given contig or replicon
• If entity is an organism, then a list is returned consisting of orthologs in the second organism of all proteins in the first organism
• An organism may be specified by any organism designation or nickname or list of organisms
• If cutoff is not specified, then an E-value of 1E-6 is used

Examples:
  (ORTHOLOG-OF all4312 IN S6803 CUTOFF 1e-10)
  (ORTHOLOG-OF (GENES-DESCRIBED-BY "cyanophycin" IN A7120) IN S6803)
  (ORTHOLOG-OF all4312 IN (Npun S6803))
  (ORTHOLOG-OF A7120 IN Npun)

          [The same result is obtained much faster by (COMMON-ORTHOLOGS-OF (A7120 Npun))]