The total level of α-tryptase and ß-tryptase in serum or plasma is used as a clinical indicator of the mast cell burden.Objective
The effect of the tryptase haplotype and of sex on the total tryptase level of healthy individuals was determined.Methods
A novel hot-stop PCR technique was used to determine the tryptase genotype, and a standard fluoroenzyme immunoassay was used to measure total plasma tryptase levels in 106 healthy subjects. Mx modeling and the QTL association routine of Mendel 5.0 were used to analyze the data.Results
Tryptase haplotypes exhibit a 1 (ßα/ßα):2 (ßß/ßα):1 (ßß/ßß) distribution, monomorphic for ß at 1 position and allelic for ß and α at the other position. The ßα haplotype has a frequency of 0.49. The ßα haplotype increases total tryptase levels by 0.5 ng/mL from the overall mean, whereas female sex increases the level by 0.2 ng/mL from the mean.Conclusion
The tryptase haplotype and sex each have a statistically significant effect on the total plasma tryptase level of healthy subjects.