Association between mast cell chymase genotype and atopic eczema: comparison between patients with atopic eczema alone and those with atopic eczema and atopic respiratory disease


Tanaka Department of Dermatology, Shiga University of Medical Science, Tsukinowa-cho, Seta, Otsu 520-2192, Japan.



It has remained unclear whether genetic background of patients with atopic eczema (AE) alone is identical to that of patients with both AE and atopic respiratory disease.


We aimed to assess whether there is a genetic difference between these two groups of AE patients.


We determined the genotype with regard to an allelic polymorphism in the gene for mast cell chymase (MCC; a serine protease secreted from mast cells) in 169 AE patients.


MCC genotype was significantly associated with pure AE patients who did not have a predisposition to atopic respiratory disease and whose serum IgE concentration was < 500 IU/mL. The distribution of MCC genotypes also differed significantly between the latter patients and those AE patients with bronchial asthma and a serum IgE concentration of > 2000 IU/mL.


These results suggest that pure AE is associated with genetic variants of MCC, and that the genetic basis of pure AE differs from that of AE associated with atopic asthma.