Al-Hussaini Abdulrahman, Alharthi Hanan, Osman Awad, Eltayeb-Elsheikh Nezar, Chentoufi Aziz
Division of Pediatric Gastroenterology, Children's Specialized Hospital, King Fahad Medical City; College of Medicine, Alfaisal University; Prince Abdullah bin Khalid Celiac Disease Research Chair, Department of Pediatrics, Faculty of Medicine, King Saud University, Riyadh, Kingdom of Saudi Arabia.
Department of Pathology and Laboratory Medicine, Division of Immunology, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia.
Saudi J Gastroenterol. 2018 Sep-Oct;24(5):268-273. doi: 10.4103/sjg.SJG_551_17.
BACKGROUND/AIM: To determine the frequency of celiac disease (CD)-predisposing human leukocyte antigen (HLA)-DQ genotypes in the Saudi population, where the prevalence of CD is 1.5% as recently reported in a mass screening study.
In a cross-sectional population-based study, a total of 192 randomly selected healthy school children (97 females, mean age 10.5 ± 2.2 years, all negative for tissue transglutaminase-IgA) were typed for D QA1 and D QB1 genes by polymerase chain reaction sequence-specific oligonucleotide probes.
Of the 192 children, 52.7% carried the high-risk CD-associated HLA-DQ molecules: homozygous DQ2.5 ( 2.6%), DQ2.5/DQ2.2 ( 4.7%), heterozygous DQ2.5 ( 28.15%), homozygous DQ8 ( 4.2%), DQ8/DQ2.2 ( 3.6%), and double dose DQ2.2 ( 9.4%). Low-risk CD-associated HLA-DQ molecules (single dose DQ2.2 and heterozygous DQ8) constituted 3.6% and 9.4%, respectively. Among the very low-risk groups, individuals lacking alleles that contribute to DQ2/DQ8 variants (33.5%), 13.5% carried only one of the alleles of the high-risk HLA-DQ2.5 heterodimer called "half-heterodimer" (HLA-DQA105 in 12% and HLA-DQB1 02 in 1.5%), and 20.8% lacked all the susceptible alleles (DQX.x). Gender distribution was not significantly different among the CD-risk groups.
We report one of the highest frequencies of CD-predisposing HLA-DQ genotypes among healthy general populations (52.7%) worldwide, which might partly explain the high prevalence of CD in the Saudi community.
背景/目的：在沙特人群中确定乳糜泻（CD）易感人类白细胞抗原（HLA）-DQ基因型的频率，在最近一项大规模筛查研究中报告沙特人群中CD患病率为1.5%。
在一项基于人群的横断面研究中，通过聚合酶链反应序列特异性寡核苷酸探针，对总共192名随机选择的健康在校儿童（97名女性，平均年龄10.5±2.2岁，组织转谷氨酰胺酶-IgA均为阴性）进行DQA1和DQB1基因分型。
在这192名儿童中，52.7%携带与CD相关的高危HLA-DQ分子：纯合DQ2.5（2.6%）、DQ2.5/DQ2.2（4.7%）、杂合DQ2.5（28.15%）、纯合DQ8（4.2%）、DQ8/DQ2.2（3.6%）和双剂量DQ2.2（9.4%）。与CD相关的低危HLA-DQ分子（单剂量DQ2.2和杂合DQ8）分别占3.6%和9.4%。在极低危组中，缺乏对DQ2/DQ8变体有贡献的等位基因的个体（33.5%），13.5%仅携带高危HLA-DQ2.5异二聚体的一个等位基因，称为“半杂合二聚体”（HLA-DQA105占12%，HLA-DQB102占1.5%），20.8%缺乏所有易感等位基因（DQX.x）。CD风险组之间的性别分布无显著差异。
我们报告了全球健康普通人群中CD易感HLA-DQ基因型的最高频率之一（52.7%），这可能部分解释了沙特社区中CD的高患病率。
