Frequency of HLA-DQA1*0501 and DQB1*0201 alleles in patients with coeliac disease, their first-degree relatives and controls in Jordan.
BACKGROUND
The primary genetic marker associated with coeliac disease (CD) is the HLA-DQ2 molecule, encoded by the DQA1*0501 and DQB1*0201 genes.


OBJECTIVE
To investigate the frequency of HLA-DQA1*0501 and DQB1*0201 alleles in Jordanian patients with CD and their first-degree relatives.


METHODS
An allele-specific DNA-based PCR-sequence-specific primer was used to investigate DQA1*0501 and DQB1*0201 alleles in 44 CD patients, 47 first-degree relatives and 53 healthy controls.


RESULTS
The mean age of the patients at the time of diagnosis was 13.5 years (range 1-39) and at the time of the study was 19.3 years (range 5-42). The DQA1/B1 (0501; 0201) haplotype was present in 80% of patients and 66% of first-degree relatives compared with 32% of controls (p<0.0001 and <0.01, respectively). The remaining 20% of CD patients who were negative for the DQ2 molecule carried the DQB1*0201 allele only. A statistically significant difference was detected in the DQ2 hetero-dimer frequency between CD patients, their first-degree relatives and controls with a higher frequency in the patients group (p<0.001).


CONCLUSIONS
The significant differences in the frequency of DQA1*0501, DQB1*0201 alleles in CD patients and their first-degree relatives compared with the control group demonstrated the important role of these alleles in the development of CD in the Jordanian population.
Departments of Biochemistry & Molecular Biology, Faculty of Applied Medical Sciences, Jordan University of Science & Technology, Irbid, Jordan. zakawi@just.edu.jo
Z J
ZJ
El-Akawi
D M
DM
Al-Hattab
M A
MA
Migdady
D000293:Adolescent; D000328:Adult; D000483:Alleles; D044466:Asian People / Q000235:genetics; D002446:Celiac Disease / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D017931:DNA Primers; D005190:Family; D005787:Gene Frequency; D005802:Genes, MHC Class II; D020022:Genetic Predisposition to Disease; D006683:HLA-DQ Antigens / Q000235:genetics*; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; D006239:Haplotypes; D006801:Humans; D007597:Jordan; D016133:Polymerase Chain Reaction / Q000379:methods; D055815:Young Adult
D017931:DNA Primers; D006683:HLA-DQ Antigens; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; C069050:HLA-DQA1 antigen; C069051:HLA-DQB1 antigen