(In my second paragraph above I'm referring of course to the in vitro tracer experiment results on the 6 patients which showed a poor conversion of tryptophan to kynurenine and which is consistent with Phair's metabolic trap hypothesis but which doesn't prove it by any means since, as implied, there are multiple other possible explanations for the results.)
I think you have a much better understanding of this than I have but here goes.
What you need is lots of data i.e. measurements of intra-cellular tryptophan (and Kynurenine?). OMF are working on methods for measuring intra-cellular tryptophan. Possibly Gulf War veterans, who have severe un-diagnosed fatigue, might get you the combination of public funding and a large population to study.
Substrate inhibition of IDO1 is relatively easy to demonstrate i.e. provided you have IDO1. Add higher levels of tryptophan to (normal levels of) IDO1 and plot the suppression of IDO1. Haven't looked at the presentation for a while but I assume that's what they did.
Getting hold of IDO2 produced by presumed non-functioning genes sounds a little bit more difficult. Really winging it here but CRISPR gene editing appears to have made it possible to edit genes more easily, so maybe it possible to produce IDO2 from these genes and then check its activity. There are now some of the best scientists in the world working on this; I assume it's deliverable i.e. if there's funding.
A method of reducing intra-cellular tryptophan also appears to be necessary i.e. to prove the trap hypothesis. Does the approach used in refeeding syndrome provide a possible way of reducing intra-cellular tryptophan? The drug which is referred to here seems interesting as well. I see OMF are working with Nancy Klimas [
https://www.omf.ngo/2017-accomplishments/]; that link (Klimas) might help to get public funding via the Gulf War veterans.
I'm not confident that problems with IDO2 will explain all of ME/CFS but it might just give an insight i.e. to make progress.
@Ben H Anyone looking at a Gulf War veteran study? I assume that many fit the diagnosis for ME/CFS.
Consider writing to your elected representative i.e. to request funding for ME/CFS research including the development of a diagnostic test.
I've written to the European Union Committee on the Environment, Public Health and Food Safety (ENVI) requesting that they lobby for funding for research into ME/CFS including the development of a diagnostic test [
https://forums.phoenixrising.me/ind...ch-theyre-working-for-you.61516/#post-1003111].
Currently the ENVI Committee is lobbying for increased funding for research into Lyme disease and the development of a diagnostic test.
In 2016 the European Commission [European Union civil service] said [regarding Lyme disease] that "
Both basic research and the development of new diagnostics, treatments and vaccines for Lyme borreliosis are funded by EU research and innovation framework programmes. The total EU contribution to such projects since 2007 amounts to EUR 33.9 million [US dollars]" [http://www.europarl.europa.eu/doceo/document/E-8-2016-008631-ASW_EN.html].
ME/CFS received no funding from the European Union [
http://www.europarl.europa.eu/doceo/document/E-8-2017-006901-ASW_EN.html].