Increased excretion of Indolyl-3-acryloylglycine (IAG) |
|
IAGThis is a compound that is derived, in the same way as many other indole compounds, from tryptophan or indole compounds in the diet as it is impossible for the body to make these basics. Unfortunately it is unclear as to exactly how it is produced and where this is taking place. We must not forget that indole compounds are produced in the gut and would be expected to be excreted following modification. We are finding IAG in the urine but the source within the body is unclear. History: It was considered a potentially useful test for autism for sometime following the work by the group in Sunderland by Shattock’s group. Their work seemed almost impossible to deny in that they had tested such a large number of cases. It was never claimed to be the absolute diagnostic test or that it’s level in the urine would be in proportion to clinical syndromes. However, the work in York by Wright et al have now carried out a large study looking at matched controls and could not show any difference between the autistic and controls. As such, at this point we cannot state that it is a
useful test unless further research is done to associate its finding with
other factors involved in autism. |
(structure of
IAG) |
Return
to Home Page
Indolyl-3-acryloylglycine in urine: a urinary
ASD marker?
Bull G, Shattock P, Whiteley P, Anderson R, Groundwater PW, Lough JW, Lees G. Indolyl-3-acryloylglycine (IAG) is a putative diagnostic urinary marker for autism spectrum disorders. Med Sci Monit. 2003 Oct;9(10):CR422-5. (this group has done the most work on the subject and is certain that it is pretty good…but there is a cross over between normal controls and ASDs..and also other mental conditions have raised IAG levels)
Wright B, Brzozowski AM, Calvert E, Farnworth H, Goodall DM, Holbrook I, Imrie G, Jordan J, Kelly A, Miles J, Smith R, Town J. Is the presence of urinary indolyl-3-acryloylglycine associated with autism spectrum disorder? Dev Med Child Neurol. 2005 Mar;47(3):190-2. IAG was found at similar levels in the urine of all children, whether IAG concentrations or IAG:creatinine ratios were compared. There was no significant difference between the ASD and the comparison group, and no difference between children at mainstream schools and those at special schools….but by this time many of the autistic kids were on casein-gluten diets. I did not get the impression that this group were specifically out to do down Shattock, who had spent many years working on this subject.
Anderson
RJ, Bendell DJ, Garnett I, Groundwater PW, Lough WJ, Mills MJ, Savery D,
Shattock PE. Identification
of indolyl-3-acryloylglycine in the urine of people with autism. J Pharm
Pharmacol. 2002 Feb;54(2):295-8
Mills
MJ, Savery D, Shattock PE. Rapid
analysis of low levels of indolyl-3-acryloylglycine in human urine by
high-performance liquid chromatography.
J Chromatogr B Biomed Sci Appl. 1998 Aug 7;712(1-2):51-8.
Return
to Home Page