[Helicobacter pylori and immunogenetic factors of the host: relevance of the HLADQA1 *0102 and *0301 alleles in peptic ulcer].
OBJECTIVE
To investigate the potential contribution of the *0102 and *0301 alleles of the HLADQA1 gene in Helicobacter pylori infection and peptic ulcer disease in a Spanish Caucasian population.


METHODS
We studied 163 patients with peptic ulcer (117 duodenal ulcers and 46 gastric ulcers; 111 with recent upper gastrointestinal hemorrhage) and 90 controls. The *0102 and *0301 alleles of the HLADQA1 gene were typed by polymerase chain reaction using genomic DNA. H. pylori infection were determined by breath test and/or serology. The cytotoxins CagA and VacA were investigated using serology (Western-blot) in 98 patients and 48 controls with H. pylori infection.


RESULTS
H. pylori infection was found in 94.6% of patients with duodenal ulcer, in 84.4% of those with gastric ulcer and in 67.4% of controls (p < 0.001). The distribution of the *0102 allele of the HLADQA1 gene was similar in patients (31.9%) and in controls (36.7%). The *0301 was more frequent in patients with gastric ulcer (32.6%) than in those with duodenal ulcer (16.2%) (p < 0.05) but no differences were found on comparison with the control group (24.4%). No differences were found when the groups were analyzed according to H. pylori infection, CagA- and VacA-positive strains, consumption of non-steroidal antiinflammatory drugs or previous history of ulcer or hemorrhage.


CONCLUSIONS
The *0102 and *0301 alleles of the HLADQA1 gene did not alter susceptibility to H. pylori infection or the evolution of peptic ulcer disease in a Caucasian population in Spain.
Santolaria
S
S
Servicio de Aparato Digestivo, Hospital Universitario de Canarias, 38291 La Laguna, Tenerife. ssantolariap@medynet.com
Barrios
Y
Y
Benito
R
R
Piazuelo
E
E
Quintero
E
E
Lanas
A
A
D000483:Alleles; D016022:Case-Control Studies; D004381:Duodenal Ulcer / Q000276:immunology* / Q000382:microbiology; D005260:Female; D006683:HLA-DQ Antigens / Q000235:genetics*; D059848:HLA-DQ alpha-Chains; D016481:Helicobacter Infections / Q000276:immunology*; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013276:Stomach Ulcer / Q000276:immunology* / Q000382:microbiology
D006683:HLA-DQ Antigens; D059848:HLA-DQ alpha-Chains; C069050:HLA-DQA1 antigen