Statement LF and DAvH analysed UK GWAS data, selected SNPs and designed assays for golden gate genotyping. Substantial contributions to sample collections were made by DAvH, LD, GKTH, PH, JRFW, DSS (UK2 cases); DPS, WLMcA (1958 cohort controls); CJM, WV, MLM (DUTCH samples); VT, FMS, COM, NPK, DK (IRISH samples). UKGWAS genotyping was performed as described in PD lab2. KAH extracted UKGWAS and UK2 celiac DNA samples and performed UK2 sample golden gate genotyping. GrahamT and AWR prepared Irish DNA samples. GrahamT, AWR and KAH performed Irish sample golden gate genotyping. UK2 and IRISH genotyping was performed in CAM lab, DP performed quality control steps. AZ prepared DUTCH celiac and control DNA samples, and AZ and JR performed DUTCH sample golden gate genotyping in CW lab. DVH and KAH performed final golden gate genotype clustering on all samples, with assistance from RG. LD and DAvH collected Paxgene RNA celiac blood samples, GH extracted Paxgene RNA, GH and MB performed expression chips in CW lab, GH and LF analysed expression data. GosiaT performed IL18RAP re-sequencing. MCW processed intestinal biopsies, MB and MCW performed expression chips in CW lab, MCW and GH analysed expression data. DJP performed analysis of genes in intestinal T cell subsets. KAH and GH performed bioinformatics and annotation of celiac risk variant regions DAvH, RMM, CW were Principal Investigators and directed respectively the UK, IRISH and DUTCH sample collections and with RJP designed overall strategy and obtained funding for the study. DAvH directed the entire study, performed statistical analysis and generated the figures. DAvH and CW wrote the paper. RMcG, FT and WMMcL performed additional statistical analysis. To identify additional celiac disease susceptibility genes, we recently tested 310,605 SNPs in a genome wide association study of 778 celiac cases and 1,422 population controls from the United Kingdom (UKGWAS), using the Illumina HumanHap300 BeadChip2. The only SNP outside the HLA region demonstrating genome-wide significance was rs13119723 on 4q27, located in a ∼500 kb block of linkage disequilibrium (LD) containing the IL2 and IL21 genes2. Independent replication of SNPs from the IL2-IL21 region was established in both Dutch and Irish collections of celiac patients and controls. We estimate, using the current markers, that the IL2-IL21 region explains less than 1% of the increased familial risk to celiac disease, suggesting that there are additional unidentified susceptibility genes. Since we observed a greater number of significantly associated SNPs in the UKGWAS than would be expected by chance, we proceeded to study >1,000 of the most significant UKGWAS association results in a further 1,643 celiac cases and 3,406 controls from three independent European celiac disease collections. This two-stage strategy, involving a joint analysis of all data, substantially reduces the genotyping requirements versus performing whole genome genotyping on all samples and has been shown to maintain sufficient statistical power3. ...

Celiac disease is a strongly heritable gastrointestinal illness that is an especially important model of the genetically complex multifactorial immune mediated diseases. The HLA component of celiac disease (a specific HLA-DQ heterodimer)is largely established and is relatively uncomplicated, and the environmental component (gluten and related grain storage proteins in the diet) is remarkably well understood. Previous family studies of celiac disease suggested that there is at least one important non-HLA locus. This locus may be a stronger genetic factor than HLA, and it apparently has a recessive mode of inheritance. We used a three step genome screening protocol to identify loci that contribute to celiac disease in the western counties of ireland, a region with the highest prevalence of celiac disease in the world. The most significant of several possible non-HLA loci that we found was on chromosome 6p about 30 cM telomeric from HLA. It has a multipoint maximum lod score of 4.66 (compared with 4.44 for HLA-DQ) and appears to have a recessive mode of inheritance. Our study localizes and provides strong evidence for linkage of at least one non-HLA locus to celiac disease and may serve as a prototype for an efficient approach to screening the human genome for loci that contribute to complex diseases.

Both TNFAIP3 (A20, at the protein level) and REL are key mediators in the nuclear factor kappa B (NF-kappaB) inflammatory signalling pathway. For the first time, a role for primary heritable variation in this important biological pathway predisposing to coeliac disease has been identified. Currently, the HLA risk factors and the 10 established non-HLA risk factors explain approximately 40% of the heritability of coeliac disease.

Aims-To investigate the prevalence of lymphocytic gastritis in patients with coeliac disease. Methods-Gastric biopsies from 70 patients with coeliac disease were examined by light microscopy for the presence of lymphocytic gastritis, defined as 25 or more intraepithelial lymphocytes/100 gastric columnar epithelial cells. Results-Lymphocytic gastritis was found in seven cases. Positive cases had a mean of 32.1 intraepithelial lymphocytes/100 columnar cells, compared with a mean of 13.9 in negative cases, and 5.15 in noncoeliac controls. No diVerences were found for age, sex, gastric corpus or antrum, or degree of inflammation in the gastric lamina propria. All intraepithelial lymphocytes were of T cell lineage. Cases not showing lymphocytic gastritis did however show significantly increased gastric intraepithelial lymphocytes compared with non-coeliac controls. Eighteen of 70 cases were positive for Helicobacter pylori, and four of seven cases of lymphocytic gastritis were H pylori positive; no significant diVerence was observed between H pylori positive and negative patients. Three cases had concomitant ulcerative enteritis, of which none showed lymphocytic gastritis, while five cases had concomitant enteropathy associated T cell lymphoma, of which one showed lymphocytic gastritis. Conclusions-Lymphocytic gastritis occurred in 10% of patients with coeliac disease. Cases without lymphocytic gastritis nevertheless showed increased gastric intraepithelial lymphocytes. Coeliac disease may on occasion be a diVuse lymphocytic enteropathy occurring in response to gluten. Lymphocytic gastritis outside coeliac disease may involve an immune response to luminal antigens, such as H pylori, not unlike the response to gluten in patients with coeliac disease. (J Clin Pathol 1998;51:207-210)

Immunoglobulin deficiency, especially deficiency of IgA, has been described in patients with celiac sprue (CS). Our study was performed in an area of high prevalence of CS to determine the prevalence of immunodeficiency states in patients with CS, to examine their clinical characteristics, response to treatment, and HLA phenotypes compared with a group of age- and sex-matched persons with CS but without immunoglobulin deficiency. Fourteen of 604 patients with CS were identified as being selectively deficient in IgA, whereas one had common variable immunodeficiency. At diagnosis, anemia was present in 8 of 14 IgA-deficient patients compared with 10 of 42 controls (p = 0.047), whereas abdominal pain was more common in controls with CS. Autoimmunity and recurrent infection were more prevalent in the IgA-deficient group. Response to gluten-free diet was similar in both groups in terms of histologic structure and recovery of intestinal brush-border enzyme activity. IgA-deficient participants with CS had no increased risk of associated malignancy or lymphoma. HLA phenotypes were similar in both groups. The prevalences of selective IgA deficiency and common variable immunodeficiency in this series of patients with CS are 2.31 in 100 and 0.16 in 100, respectively. Although this group is unique in character, close follow-up coupled with conscientious compliance with a gluten-free diet, remains the mainstay of treatment for these patients.

SUMMARY Between 1960 and 1974 the incidence of coeliac disease in children under 12 years in County Galway remained fairly constant, but since 1975 it has fallen by 62% and the lowered incidence seems well established. The number of those who were breast fed and the age at which first gluten feeding took place during the 22 years both increased significantly and from the mid-70s total protein content and osmolarity of proprietary cow's milk formulas were reduced. All three factors may be relevant. A negative correlation with the incidence of gastroenteritis was found.

Chromosomal region 2q33 encodes the immune regulatory genes, CTLA4, ICOS and CD28, which are involved in regulation of T-cell activity and has been studied as a candidate gene locus in autoimmune diseases, including coeliac disease (CD). We have investigated whether an association exists between this region and CD in the Irish population using a comprehensive analysis for genetic variation. Using a haplotype-tagging approach, this gene cluster was investigated for disease association in a case-control study comprising 394 CD patients and 421 ethnically matched healthy controls. Several SNPs, including CTLA4_CT60, showed association with disease; however, after correction for multiple-testing, CTLA4-658C/T was the only polymorphism found to show significant association with disease when allele, genotype, or carrier status frequency were analysed (carrier status (Allele C), P = 0.0016). Haplotype analysis revealed a haplotype incorporating the CD28/CTLA4 and two 5' ICOS polymorphisms to be significantly associated with disease (patients 24.1%; controls 31.5%; P = 0.035), as was a shorter haplotype composed of the CTLA4 markers only (30.9 vs 34.9%; P = 0.042). The extended haplotype incorporating CD28/CTLA4 and 5' ICOS is more strongly associated with disease than haplotypes of individual genes. This suggests a causal variant associated with this haplotype may be associated with disease in this population.

SUMMARY Lactase, sucrase, and alkaline phosphatase activities were measured in 833 peroral small intestinal biopsies from 373 patients with coeliac disease. Enzyme activities decreased with increasing degrees of mucosal damage. Enzyme activities in mucosae of patients with coeliac disease in remission were lower than in control groups matched for age, sex, and site of biopsy. Enzyme activities were measured in 81 patients when the mucosa was severely damaged and later when considerable improvement had occurred. Lactase activity remained low in 13% of patients under the age of 18 and in 33% of those over 18 years. Sucrase activity usually improved with histological recovery, but alkaline phosphatase activity tended to remain depressed in patients in whom lactase activity failed to improve.Activities of small intestinal brush border enzymes such as lactase, sucrase, and alkaline phosphatase are reduced in patients with untreated coeliac disease but recover again during remission.'-6 It has been suggested that the measurement of such enzymes may be used as a quantitative index of improvement of the small intestinal mucosa. The rates of recovery of the aforementioned enzymes vary: sucrase activity recovers more rapidly than lactase, which may remain severely depressed for many years especially in older patients.4 We have previously described the influence of age, sex, and site of intestinal biopsy on enzyme activity in control subjects.' This paper investigates the importance of these factors in a large group of patients with coeliac disease with due regard to the histological state of the intestinal mucosa. We also present an analysis of data from 81 patients where mucosal enzyme activity was examined in severely damaged mucosae and subsequently when the mucosae had improved considerably with the withdrawal of gluten from the diet. Material and methodsA total of 833 small intestinal biopsies were studied in 373 coeliac patients (218 female, 155 male) over 10 years. In all cases coeliac disease was diagnosed Accepted for publication 28 September 1983 on the basis of severe small bowel mucosal damage with histological or clinical improvement, or both, on a gluten free diet. Patients' ages ranged from 1 to 78 years, and 230 of the patients were under the age of 18 when first studied. Enzyme data are presented on biopsies from 157 patients originally on normal diets and subsequently on gluten free diets, 126 patients on gluten free diets only, and 90 patients on normal diets only. The patients were divided into three age groups: 0 to 18 years, 19 to 45 years, and 45+ years.Small intestinal biopsies were obtained and processed as previously described.7 Biopsies were obtained from the proximal duodenum (site A) in 40 cases, distal duodenum (site B) in 533 cases, and jejunum (site C) in 240 cases and were graded histologically on a scale of 0-3 as described by McNicholl and Egan.' Briefly these gradings are: grades 0/1 = normal or minor abnormalities, grade 2 = moderate mucosal damage, and grade 3 = severe mucosal dama...