Could a mouse wheel be emulated by holding Ctrl, Meta, Shift, or Alt?

The answer to this question is probably no (but it
should be yes), and this question is somewhat of a
follow-on to my previous question.

Is it possible to configure X so that the Control key
does what it normally does but if you hold it down and
then move the mouse up, you generate button 4 click
events, and if you hold it down and move the mouse
down you generate button 5 click events?

I think some applications (such as the Gimp) already
use Control + pointer movement for certain things, but
if this could be done with Meta, Alt, or Shift instead
of Control then one of those four keys would probably
work for any particular user.

If the answer to my previous question about whether or
not there is a way to map a keyboard key to button 4
is yes then mapping the Menu key to button 4 would be
satisfactory for me in conjunction with

  Option "EmulateWheelButton" "4"

in /etc/X11/XF86Config-4, but the Menu key is of
course on the right hand side of the keyboard and it
would be more comfortable to hold Control, Meta, Alt,
or Shift on the left hand side of the keyboard and
then move the pointer up or down to scroll up or down.

Thanks in advance for any advice.

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