Transparency in 2D scatter plots

Can Matlab be fooled into having variable transparency of data points in a 2D scatter plot?

My data is ultimately 5 dimensions. I have 12 countries (one color per country), 24 industries (data points or observations) , three factors (x, y and z determines the size of the point) and a time dimension for which I would like to have variable transparency (current point opaque, further back in time most transparent which is essentially a trail).

I searched and it doesn't look hopeful, but I did see where someone came up with 3D bubbles with a constant transparency. Hoping the whizzes here can help.

Answer 1

[per isakson]

I think it is doable with some low level handle graphic code. Each point should be a separate patch object (or a surface object).

[Josh]

I was afraid of that. It looks like this is probably the only solution.

Answer 2

[the cyclist]

Not sure it's possible to adjust the transparency of a marker. The answer and comment in this question may be relevant:

http://www.mathworks.com/matlabcentral/answers/10855-how-can-i-apply-variable-transparency-to-a-plot-using-scatter3

[Josh]

I did see that thread, but it wasn't clear how that would apply in the 2D case.