Abstract
The author presents data on the structure of cytochrome c genes in various organisms including the gene for a tissue-specific (testes) cytochrome c. Nucleotide sequences in introns and in noncoding regions of the gene that precede and follow the coding region are discussed, along with regulatory sequences found in these regions. The possible role of design and chance is considered in discussing the origin of the testicular cytochrome c gene and in the origin of pseudogenes. The evidence is reviewed for homology of the various functional cytochrome c genes. Also discussed is the role of presuppositions in regard to hypotheses concerning the origin of informational molecules.