Phenotype Definition, Age, and Gender in the Genetics of Asthma and Atopy

Asthma and atopy are complex genetic diseases, with gene−gene and gene−environmental interactions determining its clinical expression. It is important to use a clearly described and objective phenotype in studies on the genetics of asthma and atopy. We discuss the modifying effect of age and gender on the associations between genetic variants and the disease phenotype. Future studies should take these two inherent modifiers into account when studying the genetics of asthma in cross-sectional and longitudinal cohort studies.

a Department of Pulmonology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, Groningen 9700 RB, The Netherlands

b Department of Pediatrics, Beatrix Children's Hospital, University Medical Center Groningen, Hanzeplein 1, Groningen 9700 RB, The Netherlands

c Department of Pediatric Pulmonology, Beatrix Children's Hospital, University Medical Center Groningen, Hanzeplein 1, Groningen 9700 RB, The Netherlands

d Department of Epidemiology, University Medical Center Groningen, Hanzeplein 1, Groningen 9700 RB, The Netherlands

Corresponding author

This work was supported by a grant from Zon-Mw, The Netherlands Organisation for Health Research and Development.

PII: S0889-8561(05)00053-6

doi:10.1016/j.iac.2005.07.002

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