For a given Gene (or List of Genes) in named organism (default: D. melanogaster) returns the orthologues and the sequence of the gene(s) and orthologous genes. Optionally constrain the organism for which orthologues are shown and the data source from which the orthologue predictions are derived. Currently orthologue predictions are available from TreeFam, Panther and the Drosophila 12 genomes project. [keywords: homologue, homolog, paralogue, paralogue, ortholog]