Hi,
I have a deletion mutation as well. Here's my understanding in a nutshell;
Each gene contains a DNA sequence. DNA is a double helix made up of 4 different nucleotides (A,T,C,G - short forms, writing out the whole name makes things more confusing then they have to be). Think of DNA as a ladder. On each side of the ladder are the chains of nucleotides and the 'rungs' are bonding the nucleotides together. Now, the A nucleotide can only bind with the T nucleotide. And the C nucleotide can only bind with the G nucleotide.
Your mutation is 4382delA, which means you have a deletion of the A nucleotide at the 4382 position ('rung') of your DNA sequence. This causes a 'frame shift,' meaning that because you're missing a nucleotide, the entire sequence shifts and you therefore lose the function of the gene. (think of the T nucleotide across from the missing A nucleotide having nothing to bind to, so the rung is just kind of hanging out there, screwing up the whole order of things)
Does this make any sense at all?? I'm sure a geneticist would explain things much more eloquently, but that's my basic understanding of what's going on!