GENTECH archive


L-tryptophan: The Mayo study does not prove that GE was not the cause of EMS toxins( was Re: more on L-tryptophan)

At 16:33 1998-12-04 +0930, Rick Roush wrote:
>In terms of the claims made about L-tryptophan, the following is a case in
>point, found on the  site
>recommended by BEVERLYtang, archive 476
>" In 1989 there was an outbreak of a new disease in the US, contracted by
>over 5,000 people and traced back to a batch of food supplement produced
>with GE bacteria. Even though it contained less than 0.1 per cent of a
>highly toxic compound, 37 people died and 1,500 were left with permanent
>disabilities. The government declared that it was not GE that was at fault
>but a failure in the
>purification process, but this new toxin had never been found in non-GE
>versions of the product....."
>The latter claim is now simply not true in view of the work cited in
>published in the September issue   of the journal Nature Medicine.

Rick's conclusion is not correct. 

I have carefully read the reports in question from the Mayo Clinic: 

First, the study in questions was not on L-tryptophan but on a related
compound, 5-Hydroxy-L-Tryptophan (5-OH-Trp or 5-HTP).  

Second, the contaminants found in the 5-HTP sample were NOT IDENTICAL with
those found in the EMS case. 

To quote exactly from the text: "peak x is, in fact, a family of nearly
identical compounds. Their chemical structure is similar to two
contaminants found in the L-tryptophan linked to EMS symptoms in 1989."

Third, "peak X" has not been associated with EMS.


The only thing that we are justified to conclude from the Mayo study is
that some impurities appeared in the 5 HT samples. These were not the same
as the causative agents of EMS. The fact that they were chemically similar
does not mean that they are as dangerous or dangerous at all. In some cases
there are very  small chemical differences between harmless molecules and
powerful poisons. 

The conclusion of Rick has thus no scientific basis. 

- It has not been demonstrated that the impurities causing EMS may occur in
L-tryptophan produced by non-GE sources.

Genetic engineering, which has been experimentally shown to cause metabolic
abnormalities, remains the most probable cause of the metabolic abnormality
producing the extremely potent impurity causing EMS.

Jaan Suurkula MD

Follow-Ups: References: