The FLG mutations in 1,430 children (aged 0-18 years) with AD and 862 control subjects were genotyped by using the TaqMan assay.
RESULTS:
The FLG null mutation E2422X was not detected in any patients with AD or control subjects. The R501X null mutation was detected in only one child with AD (0.1%). Children with AD had the 3321delA deletion significantly more frequently (2.4%) than the control subjects (0.0%, P<0.001). Children with AD also had a significantly higher combined allele frequency of the three FLG null mutations (2.6%) than the controls (0.0%, P<0.001). The 3321delA null mutation did not associate significantly with AD severity (P=0.842). When the patients with AD were divided into allergic AD and non-allergic AD patient groups, these two groups did not differ in terms of the frequency of 3321delA.