PubMed Health⌕ Search

Biomedical subjects

T Dunsworth

Publications and source records attributed to T Dunsworth.

4 recordsLinked to original sources
PubMed1983

Heterozygous expression of insulin-dependent diabetes mellitus (IDDM) determinants in the HLA system.

HLA phenotypes of cases with insulin-dependent diabetes mellitus (IDDM) and identity by descent of HLA haplotypes in affected sib-pairs support an intermediate model in which morbid risk is increased by one HLA-linked IDDM determinant, and greatly increased by two determinants, which may be qualitatively different in DR3 and DR4 haplotypes. Linkage analysis allowing for gametic disequilibrium reveals no recombination in pedigrees with a DR3/DR4 propositus, but spurious recombination in the remaining pedigrees. This evidence favors interaction of unlinked IDDM determinants to produce affection in a small proportion of heterozygotes for an HLA-linked determinant. Partition of data by HLA type of the propositus (ideally by DR and the complement types jointly) is a powerful method to resolve etiological heterogeneity for HLA-associated diseases.

Adult↗
PubMed1982

Linkage disequilibrium between insulin-dependent diabetes and the Kidd blood group Jkb allele.

We studied 102 randomly ascertained probands from the Upper Midwest United States with insulin-dependent diabetes mellitus (IDDM) with respect to both HLA-DR and Kidd (Jk) markers. Based on our evidence that multiple genetic mechanisms may be involved in the etiology of IDDM the data were partitioned according to the HLA-DR phenotype, containing either two high risk antigens (DR3 or DR4) or not. Probands with two such antigens showed no applicable deviation from control frequencies, while the remainder displayed a slightly reduced relative risk for Jka (RR = 0.70, p less than .25), but a significantly elevated risk for Jkb (RR = 2.53, p less than .025). These results strongly suggest a complex model of IDDM inheritance involving, at least, one susceptibility locus in linkage disequilibrium with HLA DR3 and DR4 on chromosome 6, and a second locus in linkage disequilibrium with Jkb on chromosome 2.

Adolescent↗