Exon skipping, also known as alternative splicing is a process whereby the exons are cut from a genetic sequence (pre-mRNA or hnRNA) and rearranged multiple ways into different mRNA molecules. This allows for a single gene to code for several proteins and isoproteins. Seen in Eukaryotes only.

Yes.

A protein produced by multiple genes are cased by fusion genes.

Usually a protein is translated from a mRNA which is transcribed from a DNA. After transcription, RNA is rearranged by so-called RNA splicing in which some of short sequences are selected(Exon) or deleted(Intron). During the splicing two different genes can join together and it is called trans-splicing.

After trans-splicing, mRNA is translated into a protein, so the protein has two genes. Most cases these fusion genes are oncogenes which cause Cancerous diseases.

Jim Exon's birth name is John James Exon.

J. James Exon was born on August 9, 1921.