title: Type 1 diabetes environmental factors and correspondence analysis of HLA class II genes in the Yemenite Jewish community in Israel.
abstract: OBJECTIVE
  The Israeli Yemenite Jewish community has displayed an exceptionally rapid increase in the frequency of type 1 diabetes, having the highest rate of all Israeli ethnic groups. We studied the role of the environment, in relation to the nature and frequency of HLA class II genes, to evaluate its possible involvement in the development of diabetes.
  
  
  METHODS
  We interviewed 196 elderly Yemenite women, who had immigrated to Israel as adults, in programmed encounters about signs and symptoms of type 1 diabetes, infant feeding customs, and infectious diseases in Yemen. We also performed HLA oligotyping of DRB1, DQA1, and DQB1 genes in 120 unrelated Yemenite Jews, including 44 type 1 diabetic patients and 76 healthy control subjects, and used these data in correspondence analysis comparing Yemenites with different Israeli ethnic groups.
  
  
  RESULTS
  Interviews indicated that early exposure to cow's milk was very common in Yemen. However, none of the women could recall classical presentations of diabetes. HLA oligotyping showed that gene frequencies of non-Asp-57 (of the HLA-DQB chain) in the patients (0.94) and control subjects (0.6) were similar to those of other populations with a known high incidence of type 1 diabetes. Correspondence analysis revealed that Yemenite Jews are genetically distinct from other ethnic groups in Israel.
  
  
  CONCLUSIONS
  The genetic distinctiveness of Yemenite Jews may explain their unusually high incidence of type 1 diabetes in Israel. Despite the presence of highly susceptible diabetogenic HL4 class II genes in this community, early exposure to cow's milk did not cause phenotypic expression of diabetes in Yemen. This finding suggests that in this population, either cow's milk does not play a crucial role in triggering diabetes, or environmentally conferred protection, such as frequent infectious disease in Yemen, was dominant.
authors.affiliation: The Institute of Pediatric Endocrinology, SCMCI, Petah Tikva, Israel.
authors.forename: N
authors.initials: N
authors.lastname: Weintrob
authors.forename: E
authors.initials: E
authors.lastname: Sprecher
authors.forename: S
authors.initials: S
authors.lastname: Israel
authors.forename: O
authors.initials: O
authors.lastname: Pinhas-Hamiel
authors.forename: O J
authors.initials: OJ
authors.lastname: Kwon
authors.forename: K
authors.initials: K
authors.lastname: Bloch
authors.forename: N
authors.initials: N
authors.lastname: Abramov
authors.forename: A
authors.initials: A
authors.lastname: Arbel
authors.forename: Z
authors.initials: Z
authors.lastname: Josefsberg
authors.forename: C
authors.initials: C
authors.lastname: Brautbar
authors.forename: P
authors.initials: P
authors.lastname: Vardi
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D000818:Animals; D001224:Aspartic Acid; D002417:Cattle; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology* / Q000235:genetics* / Q000276:immunology; D004641:Emigration and Immigration; D004777:Environment; D005006:Ethnicity / Q000235:genetics; D005260:Female; D005802:Genes, MHC Class II; D005838:Genotype; D006683:HLA-DQ Antigens / Q000235:genetics*; D059866:HLA-DQ beta-Chains; D006720:Homozygote; D006801:Humans; D007223:Infant; D007225:Infant Food; D007239:Infections / Q000453:epidemiology; D007557:Israel; D007585:Jews / Q000235:genetics*; D008297:Male; D008892:Milk; D016017:Odds Ratio; D012016:Reference Values; D015006:Yemen / Q000208:ethnology
chemical_list: D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C057615:HLA-DQbeta antigen; D001224:Aspartic Acid