Psoriasis is associated with pleiotropic susceptibility loci identified in type II diabetes and Crohn disease.
BACKGROUND
Psoriasis is an immune-mediated skin disorder that is inherited as a multifactorial trait. Linkage analyses have clearly mapped a primary disease susceptibility locus to the major histocompatibility complex (MHC) region on chromosome 6p21. More recently, whole-genome association studies have identified two non-MHC disease genes (IL12B and IL23R), both of which also confer susceptibility to Crohn disease (CD).


OBJECTIVE
To ascertain the genetic overlap between these two inflammatory conditions further, we investigated 15 CD-associated loci in a psoriasis case-control dataset.


RESULTS
The analysis of 1256 patients and 2938 unrelated controls found significant associations for loci mapping to chromosomes 1q24 (rs12035082, p = 0.009), 6p22 (rs6908425, p = 0.00015) and 21q22 (rs2836754, p = 0.0003). Notably, the marker showing the strongest phenotypic effect (rs6908425) maps to CDKAL1, a gene also associated with type 2 diabetes.


CONCLUSIONS
These results substantiate emerging evidence for a pleiotropic role for s genes that contribute to the pathogenesis of immune-mediated disorders.
Wolf
N
N
Quaranta
M
M
Prescott
N J
NJ
Allen
M
M
Smith
R
R
Burden
A D
AD
Worthington
J
J
Griffiths
C E M
CE
Mathew
C G
CG
Barker
J N
JN
Capon
F
F
Trembath
R C
RC
D000328:Adult; D000483:Alleles; D016022:Case-Control Studies; D002874:Chromosome Mapping; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics; D002891:Chromosomes, Human, Pair 21 / Q000235:genetics; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics; D003424:Crohn Disease / Q000235:genetics*; D030541:Databases, Genetic; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide; D011565:Psoriasis / Q000235:genetics*