Genetic polymorphism of GSTM1 and antioxidant supplementation influence lung function in relation to ozone exposure in asthmatic children in Mexico City
- I Romieu1,
- J J Sienra-Monge2,
- M Ramírez-Aguilar1,
- H Moreno-Macías1,
- N I Reyes-Ruiz2,
- B Estela del Río-Navarro2,
- M Hernández-Avila1,
- S J London3
- 1Instituto Nacional de Salud Publica de México, Cuernavaca, Mexico
- 2Hospital Infantil “Federico Gómez”, México
- 3National Institute of Environmental Health (NIEHS), NC, USA
- Correspondence to:
Dr I Romieu
Instituto Nacional de Salud Publica, 655 Avenida Universidad, Col. Santa Maria Ahuacatitlán, 62508 Cuernavaca, Morelos, México; iromieucorreo.insp.mx
- Received 31 March 2003
- Accepted 13 August 2003
Abstract
Background: We recently reported that antioxidant supplementation with vitamins C and E mitigated ozone related decline in forced expiratory flow (FEF25–75) in 158 asthmatic children in an area with high ozone exposure in Mexico City.
Methods: A study was undertaken to determine whether deletion of glutathione S-transferase M1 (GSTM1 null genotype), a gene involved in response to oxidative stress, influences ozone related decline in FEF25–75 and the benefit of antioxidant supplementation.
Results:GSTM1 null children receiving placebo had significant ozone related decrements in FEF25–75 (percentage change per 50 ppb of ozone 2.9 (95% CI −5.2 to −0.6), p = 0.01); GSTM1 positive children did not. Conversely, the effect of antioxidants was stronger in children with the GSTM1 null genotype.
Conclusions: Asthmatic children with a genetic deficiency of GSTM1 may be more susceptible to the deleterious effects of ozone on the small airways and might derive greater benefit from antioxidant supplementation.
Footnotes
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Supported by the Mexican Sciences and Technology Council (No. 26206-M), Mexico; the National Center for Environmental Health at the Centers for Disease Control and Prevention, USA, and the Division of Intramural Research of the National Institute of Environmental Health Sciences (ZO1 ES 49019) at the National Institutes of Health, Department of Health and Human Services, USA.
