Specific HLA-DRB and -DQB alleles and haplotypes confer disease susceptibility or resistance in Bahraini type 1 diabetes patients.
Insofar as genetic susceptibility to type 1 diabetes is associated with HLA class II genes, with certain allelic combinations conferring disease susceptibility or resistance, this study assessed the distributions of HLA-DR and -DQ among 107 unrelated patients with type 1 diabetes and 88 healthy controls from Bahrain, all of Arab origin. The HLA-DRB and -DQB genotypes were determined by PCR-sequence-specific priming. The following alleles showed the strongest association with type 1 diabetes among patients versus controls according to their frequencies: DRB1*030101 (0.430 versus 0.097; P < 0.001), DRB1*040101 (0.243 versus 0.034; P < 0.001), DQB1*0201 (0.467 versus 0.193; P < 0.001), and DQB1*0302 (0.229 versus 0.091; P < 0.001). When the frequencies of alleles in controls were compared to those in patients, negative associations were seen for DRB1*100101 (0.085 versus 0.014; P < 0.001), DRB1*110101 (0.210 versus 0.060; P < 0.001), DQB1*030101 (0.170 versus 0.075; P = 0.006), and DQB1*050101 (0.335 versus 0.121; P < 0.001). In addition, the DRB1*030101-DQB1*0201 (70.1 versus 22.7%; P < 0.001) and DRB1*030101-DQB1*0302 (21.5 versus 0.0%; P < 0.001) genotypes were more prevalent among patients, thereby conferring disease susceptibility, whereas the DRB1*100101-DQB1*050101 (20.5 versus 2.8%; P < 0.001), DRB1*110101-DQB1*030101 (28.4 versus 8.4%; P < 0.001), and DRB1*110101-DQB1*050101 (30.7 versus 0.9%; P < 0.001) genotypes were more prevalent among controls, thus assigning a protective role. These results confirm the association of specific HLA-DR and -DQ alleles and haplotypes with type 1 diabetes and may underline several characteristics that distinguish Bahraini patients from other Caucasians patients.
Al-Harbi
Einas M
EM
College of Medicine, Arabian Gulf University, Manama, Bahrain.
Abbassi
Abdul-Jabbar
AJ
Tamim
Hala
H
al-Jenaidi
Fayza
F
Kooheji
Mariam
M
Kamal
Madeeha
M
al-Mahroos
Salwa
S
al-Nasir
Faisal
F
Motala
Ayesha A
AA
Almawi
Wassim Y
WY
D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000097:blood; D001445:Bahrain; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics* / Q000276:immunology*; D004198:Disease Susceptibility / Q000276:immunology; D005260:Female; D005787:Gene Frequency; D006683:HLA-DQ Antigens / Q000235:genetics* / Q000276:immunology; D059866:HLA-DQ beta-Chains; D006684:HLA-DR Antigens / Q000235:genetics* / Q000276:immunology; D059811:HLA-DRB1 Chains; D006239:Haplotypes; D006801:Humans; D007223:Infant; D008297:Male
D001323:Autoantibodies; D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; C553518:HLA-DRB1*11:01:01 antigen