Association of the PD-1.3A allele of the PDCD1 gene in patients with rheumatoid arthritis negative for rheumatoid factor and the shared epitope.
OBJECTIVE
To study the frequency of allele A of polymorphism PD-1.3 of the PDCD1 gene in patients with rheumatoid arthritis (RA) and its subsets, based on the presence of rheumatoid factor (RF) and the shared epitope (SE) alleles.


METHODS
A total of 1,175 patients with RA and 3,404 controls were genotyped for the PD-1.3 A/G polymorphism, which previously was identified as being involved in susceptibility to systemic lupus erythematosus (SLE) in patients of European descent.


RESULTS
We first detected a trend for association of allele A of the single-nucleotide polymorphism PD-1.3 with RA (P = 0.053, odds ratio [OR] 1.18, 95% confidence interval [95% CI] 0.99-1.41). To further clarify the nature of this association, patients with RA were divided into 4 groups according to the presence of RF and the SE alleles. Association was found only in the group of patients negative for both RF and the SE alleles (P = 0.0054 [corrected P = 0.015], OR 1.75, 95% CI 1.15-2.65).


CONCLUSIONS
Patients negative for both RF and the SE alleles showed association with the same allele that we previously identified as being involved in susceptibility to SLE. These results provide the first evidence of the involvement of the human PDCD1 gene in arthritis.
Prokunina
Ludmila
L
Uppsala University, Uppsala, Sweden.
Padyukov
Leonid
L
Bennet
Anna
A
de Faire
Ulf
U
Wiman
Björn
B
Prince
Jonathan
J
Alfredsson
Lars
L
Klareskog
Lars
L
Alarcón-Riquelme
Marta
M
D015703:Antigens, CD; D000954:Antigens, Surface / Q000235:genetics*; D051017:Apoptosis Regulatory Proteins; D001172:Arthritis, Rheumatoid / Q000235:genetics*; D000939:Epitopes / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D061026:Programmed Cell Death 1 Receptor; D012217:Rheumatoid Factor / Q000235:genetics*; D013548:Sweden
D015703:Antigens, CD; D000954:Antigens, Surface; D051017:Apoptosis Regulatory Proteins; D000939:Epitopes; C105992:PDCD1 protein, human; D061026:Programmed Cell Death 1 Receptor; D012217:Rheumatoid Factor