Polymorphisms in SPINK5 are not associated with asthma in a Dutch population.

Asthma and allergic phenotypes are complex genetic diseases with known linkage to chromosome 5q. This region has many candidate genes, including serine protease inhibitor Kazal type 5 (SPINK5), which has been associated with asthma and atopic dermatitis in family-based studies of children with atopic dermatitis. We sought to investigate whether single nucleotide polymorphisms in SPINK5 are associated with asthma, atopic phenotypes, and atopic dermatitis. We investigated whether single nucleotide polymorphisms in SPINK5 (ie, -785 A/G, Asn368Ser, and Lys420Glu) are associated with asthma, atopic phenotypes, and atopic dermatitis in 200 families ascertained by a proband with asthma (nonaffected spouses served as a matched control population) and an independent set of 252 trios with asthma. We found no association with asthma, atopic phenotypes, and atopic dermatitis after correction for multiple testing. The negative results in this study suggest that SPINK5 is not associated with asthma or atopic phenotypes in individuals ascertained by a proband with asthma. This is consistent with the finding that SPINK5 is not expressed in the lung. Because our patients were ascertained for asthma, a role of SPINK5 in atopic dermatitis cannot be excluded.