Nested Genes - A nested gene is a gene which produces two proteins simultaneously from a long single transcript by changing the end point of protein synthesis.

This can occur by leaky read through of a termination codon or by co translation frame shifting.

F-plasmid, tra X-gene and eukaryotic RNA viruses use similar strategies.

Nested products can also be produced from eukaryotic genes by alternative splicing or by the use of alternative polyadenylation sites.