Interleukin-10 promoter polymorphism in psoriasis.
Beneficial effects of interleukin-10 therapy and lower endogenous interleukin-10 formation compared with atopic dermatitis and cutaneous T cell lymphomas indicated that interleukin-10 is a key cytokine in psoriasis. The interleukin-10 promoter is highly polymorphic, with two informative microsatellites, interleukin-10.G and interleukin-10.R. In order to understand whether interleukin-10 itself is a predisposing gene for the psoriasis susceptibility we analyzed interleukin-10 promotor polymorphism in patients. The distribution of interleukin-10.G and interleukin10.R microsatellite alleles did not vary between patients (n = 78) and healthy controls (n = 80). In addition, when the psoriasis patients were stratified according to age of onset (younger than 40 y of age, or age 40 and older), no difference in allele distribution was observed; however, a clear differential distribution was revealed at the interleukin10.G locus when patients were stratified according to whether they had a positive family history of psoriasis (p = 0.04). This difference was due to an over-representation of the interleukin10.G13 allele in those patients with familial disease (40.4% vs 19.6%, Chi-square = 7.292, p = 0.007). The positive association of allele interleukin10.G13 with familial psoriasis was especially true when patients with an early onset (< 40 y of age) of the disease were compared with those patients with early onset against a nonfamilial background (39.6% vs 14.5%, Chi-square = 8.959, p = 0.003). Patients with age-of-onset of less than 40 were 4-fold [odds ratio = 3.85 (1.55--9.62)] more likely to have a psoriatic family background if they carried this interleukin10.G13 allele. These data suggest that the interleukin-10 locus contributes to the heritability of psoriasis susceptibility.
Asadullah
K
K
Department of Dermatology, Medical School Charité, Humboldt University Berlin, Berlin, Germany. khusru.asadullah@schering.de
Eskdale
J
J
Wiese
A
A
Gallagher
G
G
Friedrich
M
M
Sterry
W
W
D000483:Alleles; D020022:Genetic Predisposition to Disease; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics*; D018895:Microsatellite Repeats; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D011565:Psoriasis / Q000235:genetics*
D016753:Interleukin-10