PHF11 is not a major candidate gene for asthma or eczema in Chinese children

Positional cloning and candidate gene studies in different Caucasian populations identified the gene encoding plant homeodomain zinc finger protein 11 (PHF11) to be associated with asthma and eczema. Microarray analysis also confirmed increased PHF11 expression in type 1 T-helper lymphocytes. However, such disease associations are unclear in Asian subjects. This case-control genetic association study investigated the relationship between asthma and eczema phenotypes and tagging single-nucleotide polymorphisms (SNPs) of PHF11 in Hong Kong Chinese children. Three hundred and nineteen asthmatic children and 236 children with eczema were recruited from hospital clinics and 445 children without any history of allergic disease were recruited as controls from local schools and hospitals. Atopy was defined by the presence of allergen-specific IgE in plasma or positive skin prick tests with wheal >or=3 mm larger than negative control. Lung function of asthmatics was evaluated by pre-bronchodilator spirometry. Ten PHF11 SNPs were genotyped by multiplex SNaPshot assay. Genotyping call rates were 100% for all SNPs, which also followed Hardy-Weinberg equilibrium. These SNPs were tightly linked in one haplotype block (D' >or= 0.95 for nearly all SNP pairs). Physician-diagnosed asthma was weakly associated with PHF11 +20860 and +22818 (P = 0.032 for both). Atopy was also associated with PHF11 +22398 (P = 0.029). However, none of the PHF11 SNPs was associated with eczema diagnosis and plasma total IgE and spirometric parameters in our patients. Our findings do not support PHF11 to be a major candidate gene for asthma, eczema and aeroallergen sensitization in Chinese children.