MATLAB demosaic function modification?

Hello,

I have an image sensor that has a pseudo Bayer pattern. Instead of the standard green/red/blue/green layout one of the green pixels is replaced by a white pixel. What I would like to do, ideally, is 'modify' the in-built demosaic algortihm to account for this. The problem is i am not sure if this is possible and if it is so I guess it will be non-trivial.

Any help is most welcome. Thanks!