Look up one value, and return long column

Hi there,
I think this ones a complicated one.

I want to look up one cell value across a number of headings, and then return the whole column and values below that heading. I've attached an example work sheet.

In this example I want to look at the cell next to 'Variable:' and return the list of values below that cell where I have put ?marks.

Example sheet.xlsx

This look up will be to a different work sheet. The end goal will be for me to change the variable that is look up (perhaps to x, or v, or y) and return the corresponding column.

If in addition the column values could be transposed in the formula to result in a row of the same values that would also be grateful.

Thanks in advance. Rep to annoying who helps a struggling man!

D