Case-control study of genotypes in multiple chemical sensitivity: CYP2D6, NAT1, NAT2, PON1, PON2 and MTHFR

Abstract

A genetic predisposition for MCS may involve altered biotransformation of environmental chemicals. The CYP2D6 enzyme activates and inactivates toxins; the NAT2 enzyme bioactivates arylamines to protein-binding metabolites. A gene-gene interaction between CYP2D6 and NAT2 suggested that rapid metabolism for both enzymes may confer substantially elevated risk (OR = 18.7, P = 0.002). Our finding parallels others' observation of a link between PON1 heterozygosity and neurological symptoms in Gulf War syndrome. This first demonstration of genetic variation in drug-metabolizing enzymes in association with MCS requires replication. However, it suggests new research directions on genetically variable toxin pathways that might be important in MCS.

Factors in genetic susceptibility in a chemical sensitive population using QEESI

“…Previous studies suggested that the polymorphic site in PON1 was related to an increased risk of MCS [23] and Gulf War Syndrome, which is an MCSrelated syndrome [15]. However, no significant association between the Gln192Arg polymorphism and PON1 was obtained in our study.…”

“…Several reports suggest that MCS patients who are aware of their chemical intolerance avoid exogenous chemicals such as those from smoking [23,24]. Tobacco smoke contains many kinds of chemicals, including formaldehyde and acetaldehyde [25].…”

Clinical problems in patient with Ehlers-Danlos syndrome and Multiple Chemical Sensitivity undergoing total thyroidectomy

“…Thanks to the study of genetic polymorphisms, particularly regarding the enzymes involved in the metabolism of drugs and substances commonly used in the perioperative period, it was possible to obtain the definition of the genotype associated with each enzyme and to perform, than, a prediction and estimate of the impact on the metabolism of each classes of drugs (8). In the study were also included some transporter proteins for drugs within the liver microsomes (ABCC1 and 2) and enzymes responsible for the control of intracellular oxidative stress, indirect indicator of metabolic overload.…”

The feasibility of aromatherapy massage to reduce symptoms of Idiopathic Environmental Intolerance: A pilot study

“…There are several studies underway to determine the aetiological source of IEI. Genetic polymorphisms in drug-metabolising enzymes have previously been examined; 12,13 however, genetic involvement in IEI remains unclear.…”

“…Experimental exposures to various chemicals, [12][13][14][15] as well as studies of groups at high risk for chemical exposures, 16 have also failed to identify any differences between IEI patients and control subjects. Thus, the hypothesis that frequent chemical exposure causes an increased risk for developing IEI has not yet been confirmed.…”