Eliminating "hidden" keyboard shortcut

Using iMac with SL and wireless keyboard. When I type fast and accidently hit shift and up arrow a line of text to the left of the cursor is highlighted and erased with the next keystroke. How do I turn off this "shortcut", shift plus the up arrow?
Thanks.

You can't as far as I know. The shift+arrow key is primarily for highlighting text.

- Simon

Maybe you could reassign the shortcuts in some manner?

Eliminating "hidden" shortcut

Thanks to all. It is annoying when pressing the right shift key my 5th finger droops down and touches the up arrow and highlights the text from the point of the last insertion. Generally, I'm not looking at the screen so I don't notice the highlighted text and so the next keystroke deletes it.

I am learning to live with it!

Peels

If it gets deleted just do "cmd+z" to undo, a pain I know I do the same thing now and again, just got to live with my fat fingers lol

- Simon