FLG single nucleotide polymorphisms in chronic idiopathic urticaria

Background: Filaggrin (FLG), which is formed from profilaggrin protein during epidermal terminal differentiation, is a prerequisite to squame biogenesis and thus for perfect formation of the skin barrier. Yet, the relationship between genetic polymorphisms of FLG and chronic idiopathic urticaria (CIU) has not been investigated.

Methods: The study population consisted of 93 CIU patients and 93 healthy control subjects without a history of allergic, autoimmune or any other systemic disease. Five single nucleotide polymorphisms (SNPs) of FLG were investigated: rs2485518, rs3126065, rs2786680, rs3814300, and rs3814299.

Results: For all the investigated polymorphisms, 100% of both CIU patients and control subjects exhibited one given allele and consequently one given genotype as following: A/A genotype for two SNPs, rs3126065 and rs2786680, C/C genotype for two SNPs, rs2485518 and rs3814300, and G/G genotype for one SNP rs3814299 of FLG, and hence no association was found between either allele frequencies or genotype distributions of FLG SNPs and CIU in an Iranian population.

Conclusions: The present study examined the possible relationship between SNPs of FLG and CIU for the first time, and demonstrated that none of five investigated SNPs (rs2485518, rs3126065, rs2786680, rs3814300, and rs3814299) are correlated with CIU in an Iranian population. Further investigations are required to address whether ethnicity/race impacts on relationship between SNPs of FLG and CIU.