Association study of LMP gene polymorphisms in Mexican patients with spondyloarthritis.
To evaluate the role of LMP (low molecular weight protein) genes as susceptibility markers for spondyloarthritis (SpA), LMP gene polymorphisms were analyzed in 223 Mexican patients with SpA (81 undifferentiated SpA [U-SpA], 117 with ankylosing spondylitis [AS], 25 with reactive arthritis) and in 139 ethnically matched healthy individuals. LMP genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism. The LMP2 and LMP7 allele frequencies were similar in patients and healthy controls. Genotype analysis revealed an increased frequency of LMP2 R/R genotype in the whole group of SpA (pC = 0.003, OR = 2.06, 95%CI = 1.3-3.25) and in the clinical subgroups of AS (pC = 0.039, OR = 1.88, 95%CI = 1.1-3.22) and U-SpA (pC = 0.003, OR = 2.56, 95%CI = 1.37-4.8) compared with healthy controls. Analysis in the LMP7 did not reveal significant differences in patients and healthy controls. The HLA-B27-negative AS subgroup also showed an increased frequency of LMP2 R/R genotype (pC = 0.027, OR = 4.81, 95%CI = 1.21-22.13). The LMP2-R/R AS patients were younger than LMP2-H/R and H/H patients at onset of the disease (16.0 +/- 6.8 years for R/R, 22.0 +/- 11.2 years for H/R and 28.6 +/- 10.9 years for H/H) (p < 0.05). The data suggest that, besides HLA-B27, LMP2 genotypes are also involved in the genetic susceptibility to develop AS in Mexicans. Furthermore, the age at onset of this disease might also be influenced by genotypes of this gene.
Vargas-Alarcón
Gilberto
G
Department of Physiology, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City, Mexico. gvargas63@yahoo.com
Gamboa
Ricardo
R
Zuñiga
Joaquín
J
Fragoso
José Manuel
JM
Hernández-Pacheco
Guadalupe
G
Londoño
John
J
Pacheco-Tena
Cesar
C
Cardiel
Mario H
MH
Granados
Julio
J
Burgos-Vargas
Rubén
R
D000293:Adolescent; D000328:Adult; D000483:Alleles; D016918:Arthritis, Reactive / Q000201:enzymology / Q000235:genetics / Q000276:immunology; D001483:Base Sequence; D016022:Case-Control Studies; D003546:Cysteine Endopeptidases / Q000235:genetics*; D004247:DNA / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D015796:HLA-B27 Antigen / Q000235:genetics; D006801:Humans; D008297:Male; D008800:Mexico; D009097:Multienzyme Complexes / Q000235:genetics*; D011110:Polymorphism, Genetic; D046988:Proteasome Endopeptidase Complex; D025242:Spondylarthropathies / Q000201:enzymology / Q000235:genetics* / Q000276:immunology; D013167:Spondylitis, Ankylosing / Q000201:enzymology / Q000235:genetics / Q000276:immunology
D015796:HLA-B27 Antigen; D009097:Multienzyme Complexes; C071313:LMP-2 protein; D004247:DNA; D003546:Cysteine Endopeptidases; C077436:LMP7 protein; D046988:Proteasome Endopeptidase Complex