Ever since the pioneering work of the Khorana group that synthesized the 77-bp nucleotide gene encoding a yeast alanine transfer RNA and the 207-bp gene for the tyrosine suppressor tRNA 40 years ago, scientists have had the ability to join DNA sequences and produce combinations that are not present in nature.Recently, chemical synthesis of genes has become routine, and the chemical synthesis of genomes has now become a reality and several viral genomes generated by the chemical synthesis have been reported.