GenomeDescription-class
                        GenomeDescription objects
Seqinfo-class           Seqinfo objects
available.species       Returns a data.frame that lists the available
                        species strings and their taxonomy Ids.
fetchExtendedChromInfoFromUCSC
                        Fetching chromosomes info for some of the UCSC
                        genomes
rankSeqlevels           Assign sequence IDs to sequence names
seqinfo                 Accessing/modifying sequence information
seqlevels-wrappers      Convenience wrappers to the seqlevels() getter
                        and setter
seqlevelsStyle          Conveniently rename the seqlevels of an object
                        according to a given style
speciesMap              Species Mapper object and/or list of valid
                        taxonomy Ids