The association between the IL-20-1723C→G allele on the 1q chromosome and psoriasis triggered or exacerbated by an upper respiratory tract infection in the Chinese Han population.
BACKGROUND
Psoriasis is a cutaneous disorder of multifactorial etiology influenced by both genetic and environmental factors such as infection.


METHODS
We conducted a genome analysis with 20 microsatellite markers spanning the long arm of chromosome 1 in 36 Chinese families with psoriasis and detected evidence for linkage at 1q21 with a nonparametric linkage score of 1.74, p=0.03, and 1q32 with one of 1.84, p=0.03. According to the positional and functional candidate principle, we further investigated the single-nucleotide polymorphisms of the HAX-1 gene (located in 1q21) and IL-20 gene (located in 1q32) in a case-control study including 340 sporadic patients and 199 controls.


RESULTS
We determined that the frequency of the G allele of IL-20-1723C→G (rs1713239) was significantly higher among psoriatic patients (38.5% in cases vs. 31.2% in controls, p=0.015, odds ratio, OR=1.39, 95% confidence interval, CI=1.07-1.80). When we stratified our analysis by psoriasis triggered or exacerbated by infection of the upper respiratory tract, a significant difference was detected (42.4% in stratified cases vs. 31.2% in controls, p=0.005, OR=1.63, 95% CI=1.15-2.30).


CONCLUSIONS
We assume that triggered or exacerbated by respiratory tract infection, the population with the G allele of IL-20-1723C→G are predisposed to psoriasis.
Department of Dermatology, Ruijin Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China.
Xiao-Ying
XY
Chen
Li-Wei
LW
Jin
Ying-Wei
YW
Chen
Han
H
Tian
Wen-Tao
WT
Yuan
Zhen-Min
ZM
Niu
Jing
J
Zhang
Wie
W
Huang
Jie
J
Zheng
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D016022:Case-Control Studies; D002648:Child; D002878:Chromosomes, Human, Pair 1; D005260:Female; D020022:Genetic Predisposition to Disease; D055106:Genome-Wide Association Study; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011565:Psoriasis / Q000150:complications* / Q000235:genetics*; D012141:Respiratory Tract Infections / Q000150:complications*; D055815:Young Adult