Atopic eczema is a common inflammatory skin disease with multifactorial etiology. The genetic basis is incompletely understood; however, loss of function mutations in the filaggrin gene (FLG) are the most significant and widely replicated genetic risk factor.
The first genome-wide association study in atopic eczema recently identified 2 novel genetic variants in association with eczema susceptibility:
- a single nucleotide polymorphism (SNP) on chromosome 11q13.5
- a single nucleotide polymorphism (SNP) within the gene encoding hornerin on chromosome 1q21
The 4 most common FLG null variants were strongly associated with atopic eczema.
The 11q13.5 (rs7927894) association was independent of the well-established FLG risk alleles and may be multiplicative in its effect.
There was no association between 1q21/rs877776 and pediatric eczema in this study.
Chromosome 11q13.5 variant associated with childhood eczema: An effect supplementary to filaggrin mutations. O'Regan GM, Campbell LE, Cordell HJ, Irvine AD, McLean WH, Brown SJ. J Allergy Clin Immunol. 2010 Jan;125(1):170-174.e2.
Image source: Chromosome 11 Chart. Wikipedia, public domain.