No remarkable differences in rates of sensitization to common type I and IV allergens between FLG loss-of-function mutation carriers and wild-type subjects.

Background: Loss-of-function mutations in the filaggrin gene (FLG) have been associated with reduced skin barrier function, possibly allowing increased penetration of irritants and allergens.

Objectives: To study whether FLG loss-of-function mutation carriers show different rates of sensitization to common type I and IV allergens among patients referred for occupational contact dermatitis of the hands.

Materials And Methods: Four hundred and ninety-six Caucasian patients were genotyped for four FLG null mutations and patch tested with the European baseline series. In addition, 431 patients underwent prick testing with common type I allergens.

Results: Overall, 67 patients showed a heterozygous mutation in the FLG alleles R501X, R2447X, S3247X, and/or 2282del4. Sensitization rates for type I allergens from a European prick test series did not show significant differences between FLG loss-of-function mutation carriers and wild-type subjects. For type IV allergens, significantly more FLG loss-of-function carriers were found to be sensitized to lanolin and p-tert-butylphenol-formaldehyde resin.

Conclusions: Probably a variety of immunological mechanisms other than that resulting from the filaggrin system have an impact on allergic sensitization to a greater degree. Larger cohorts may be necessary to increase the statistical power of the findings presented regarding type I and IV sensitization.