1. ¹St John's Institute of Dermatology, King's College London, St Thomas's Hospital, London, UK
2. ²Biomedical Research Center, Population Pharmacogenetics Group, Biomedical Research Centre, University of Dundee, Ninewells Hospital and Medical School, Dundee, UK
3. ³Division of Pathology and Neuroscience, Epithelial Genetics Group, Human Genetics Unit, Division of Pathology and Neuroscience, University of Dundee, Ninewells Hospital and Medical School, Dundee, UK
4. ⁴Department of Dermatology, University of Newcastle upon Tyne, Newcastle upon Tyne, UK
5. ⁵Deparment of Medical and Molecular Genetics, King's College London, London, UK

Correspondence: Professor William H.I. McLean, Epithelial Genetics Group, Human Genetics Unit, Division of Pathology and Neuroscience, University of Dundee, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK. E-mails: w.h.i.mclean@dundee.ac.uk; jonathan.barker@kcl.ac.uk

Received 27 July 2006; Revised 22 August 2006; Accepted 23 August 2006; Published online 21 September 2006.

Abstract

Atopic dermatitis (AD) is a common disease with a complex etiology in childhood and adult life. A significant proportion of childhood AD is transient, but in many cases it persists into adulthood. We have recently shown that null mutations in the filaggrin gene (FLG) are an important predisposing factor for childhood eczema and eczema-associated asthma, but persistence to adulthood has not been analyzed. Here we studied a cohort of adult patients with persistent AD, which had been present since early childhood. In this cohort, the combined allele frequency of the two common FLG null variants was 0.270 (cf. population frequency 0.046). This represents an odds ratio of 7.7 with 95% confidence interval of 5.3–10.9 and a ² P-value of 1.7 10^-53. Our data conclusively demonstrate that identification of FLG null alleles is an indicator of a poor prognosis in AD, predisposing to a form of eczema that starts in early infancy and persists into adulthood. This study helps to further define the nature of the AD phenotype associated with FLG null alleles.