Insulin-gene sharing in sib pairs with insulin-dependent diabetes mellitus: no evidence for linkage
- PMID: 2892397
- PMCID: PMC1715306
Insulin-gene sharing in sib pairs with insulin-dependent diabetes mellitus: no evidence for linkage
Abstract
An association between insulin-dependent diabetes mellitus (IDDM) and an RFLP adjacent to the insulin gene has been consistently observed, but its etiological significance is unclear. We studied unrelated IDDM patients (N = 45) and controls (N = 65) to confirm the association--and assessed evidence for linkage in 22 families with at least two affected (IDDM) sibs--to determine whether the insulin-gene region actually contributes to susceptibility to IDDM. All individuals were typed for the RFLP in the 5'-flanking region of the insulin gene (5'FP) used in the previous studies, and the 12 families not fully informative for linkage with the 5'FP were typed for additional closely linked RFLPs. We found a higher frequency of class 1 alleles of the 5'FP in IDDM patients (.83) than in controls (.75), which is consistent with the reported association, but the difference was not statistically significant in our sample. Among the 33 affected sib pairs (ASPs) in 22 families, if maximum possible sharing is assumed when sharing is ambiguous, 10 pairs share both parental insulin genes, 17 pairs share one, and six share neither. This distribution is incompatible with close linkage. In contrast, for the HLA region, for which all 22 families are fully informative, 19 of the 33 ASPs share two haplotypes and the remaining 14 share one. There are no pairs that share neither HLA haplotype. Thus, although these data clearly illustrate the contribution of HLA-linked susceptibility to IDDM, they argue strongly against a contribution of similar magnitude by the insulin-gene region.
Similar articles
-
Transmission test for linkage disequilibrium: the insulin gene region and insulin-dependent diabetes mellitus (IDDM).Am J Hum Genet. 1993 Mar;52(3):506-16. Am J Hum Genet. 1993. PMID: 8447318 Free PMC article.
-
The insulin gene and susceptibility to IDDM.Genet Epidemiol. 1989;6(1):65-9. doi: 10.1002/gepi.1370060113. Genet Epidemiol. 1989. PMID: 2567260
-
T-cell receptor genes and insulin-dependent diabetes mellitus (IDDM): no evidence for linkage from affected sib pairs.Am J Hum Genet. 1990 Jul;47(1):45-52. Am J Hum Genet. 1990. PMID: 1971998 Free PMC article.
-
Non-HLA region genes in insulin dependent diabetes mellitus.Baillieres Clin Endocrinol Metab. 1991 Sep;5(3):413-38. doi: 10.1016/s0950-351x(05)80139-9. Baillieres Clin Endocrinol Metab. 1991. PMID: 1909861 Review.
-
Insulin gene in diabetes. Analysis through RFLP.Diabetes Care. 1990 Mar;13(3):364-74. doi: 10.2337/diacare.13.3.364. Diabetes Care. 1990. PMID: 1968374 Review.
Cited by
-
The TDT and other family-based tests for linkage disequilibrium and association.Am J Hum Genet. 1996 Nov;59(5):983-9. Am J Hum Genet. 1996. PMID: 8900224 Free PMC article. Review. No abstract available.
-
Mapping disease genes: family-based association studies.Am J Hum Genet. 1995 Aug;57(2):487-98. Am J Hum Genet. 1995. PMID: 7668275 Free PMC article.
-
The genes influencing the susceptibility to IDDM in humans.J Endocrinol Invest. 1994 Jul-Aug;17(7):477-95. doi: 10.1007/BF03347743. J Endocrinol Invest. 1994. PMID: 7829823 Review. No abstract available.
-
Genetic predisposition to IDDM.Clin Rev Allergy Immunol. 2000 Dec;19(3):227-46. doi: 10.1385/CRIAI:19:3:227. Clin Rev Allergy Immunol. 2000. PMID: 11138407 Review. No abstract available.
-
The aggregation of the 5' insulin gene polymorphism in insulin dependent (type I) diabetes mellitus families.J Med Genet. 1992 Jul;29(7):447-50. J Med Genet. 1992. PMID: 1353534 Free PMC article.
References
Publication types
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Full Text Sources
Medical
Research Materials