My response to your question is inexplicably being blocked from posting, so I've attached it as a PDF file. Please let me know if you can't access it or if you have any other follow-up questions/comments. Hope this helps!
Introns are parts of genes that do not directly code for proteins. (2)
Exons are parts of DNA that are converted into mature messenger RNA (mRNA). (6) The process by which DNA is used as a template to create mRNA is called transcription.
The exact cause is not known It mihht be 2 or more diseases not yet defined
