Characterization of MHC ancestral haplotypes associated with insulin-dependent diabetes mellitus: evidence for involvement of non-HLA genes.

Insulin-dependent diabetes mellitus (IDDM) is associated with several DR3- or DR4-containing ancestral haplotypes (AHs). Using pulsed field gel electrophoresis (PFGE), long range maps of 35 haplotypes have been derived and classified. Two diabetogenic DR3-containing AHs (8.

Supratypes and ancestral haplotypes in IDDM: potential importance of central non-HLA MHC genes.

Juvenile insulin-dependent diabetes mellitus develops in susceptible children exposed to unknown environmental factors. If the genes responsible for susceptibility could be identified, it should be possible to understand the method of injury to beta cells as well as identify the infectious or other agents involved. For a decade it has been known that one or more of the susceptibility genes must be within the major histocompatibility complex (MHC).

Comparative mapping of the human major histocompatibility complex in different racial groups by pulsed field gel electrophoresis.

The molecular map of the human major histocompatibility complex was examined in multiple examples of various Caucasoid and Japanese major histocompatibility complex supratypes using pulsed field gel electrophoresis. Extensive differences in restriction fragment lengths were observed. However, each supratype showed specific genomic characteristics including deletions, duplications, or insertions supporting the hypothesis that these supratypes are markers of conserved ancestral haplotypes.

Extensive deletions and insertions in different MHC supratypes detected by pusled field gel electrophoresis.

The genomic organization of the human MHC was examined in multiple examples of six different supratypes using pulsed field electrophoresis (PFGE) after digestion of genomic DNA with infrequency cutting restriction endonucleases. Differences in restriction fragment length and band intensity were shown to be specific for each supratype. Mapping of the MHC revealed that each supratype contains previously undescribed deletions and insertions between HLA B and DQ regions.

Population study of heterophile antibodies.

Sera from 2,829 participants in a population health survey were tested for the presence of a heterophilic antibody, detectable by immunofluorescence. The antibody was found in 9.8% of the sera from women and in 12.