I'm totally out of my league here scientifically, but looking at Kerr's gene expression papers, the distinctions between the different groups' symptoms don't seem terribly clear cut. From having just read the media reports, I really expected this to have an impact on further CFS research - eg: seeing if graded exercise etc is helpful for certain groups and not others. Instead it seems to have been rather passed by. Looking back at the orginial paper, I feel I understand better why it hasn't had the influence I expected. Is this just me having misguided notions as to how science like this works? Is it sensible to talk of CFS patients as falling into clearly identifiable distinct groups? How normal is it for patients with other chonic illnesses to have similar diferences in symptoms and gene expression?