Allelic variation in class I K gene as candidate for a second component of MHC-linked susceptibility to type 1 diabetes in non-obese diabetic mice.

AIMS/HYPOTHESIS: Recent studies have revealed that MHC-linked susceptibility to Type 1 diabetes is determined by multiple components. In the non-obese diabetic (NOD) mouse, a second component (Idd16) has been mapped to a region adjacent to, but distinct from Idd1 in the class II region. In this study, we investigated the class I K gene as a candidate gene for Idd16. METHODS: We determined the genomic sequences of the class I K gene as well as the reactivity of K molecules with monoclonal antibodies in the NOD mouse, the Cataract Shionogi (CTS) mouse, and the NOD.CTS-H-2 congenic strain, which possesses a resistance allele to Type 1 diabetes at the Idd16 on the NOD genetic background genes. RESULTS: While the K sequence of the NOD mouse was identical to that of Kd type, ten nucleotide substitutions were identified in the CTS mouse compared with the NOD mouse. Of these, three were in exon 4, giving two amino acid substitutions, which were identical to those seen in KK type. These characteristics were retained in the NOD.CTS-H-2 congenic strain, which had a lower incidence and delayed onset of Type 1 diabetes owing to a resistance allele at Idd16. Lymphocytes from NOD.CTS-H2 congenic mice reacted with anti-Kd and anti-Kk monoclonal antibodies, reflecting the unique sequence of the K gene. The nucleotide sequence of the K gene in the non-obese non-diabetic (NON) mouse was also unique, consisting of a combination of Kk- and Kb-like sequences. CONCLUSIONS/INTERPRETATION: These data suggest that H2-K is unique in CTS and NON mice, and that allelic variation of the class I K gene may be responsible for Idd16.

[Prevalence of Raynaud's phenomenon in individuals not using vibrating tools].

Vibration syndrome, especially Raynaud's phenomenon, has generally been observed in vibrating tool operators, but the frequency of Raynaud's phenomenon in individuals not using vibrating tools is unknown. The authors therefore conducted a survey on the prevalence of stiffness of hands, numbness of fingers, and Raynaud's phenomenon among the examinees of Gifu Prefectural Health Care Center and among the female students of Gifu Prefectural Nursing and Paradental School. The following results were obtained by this survey. 1. Prevalences of stiffness of hands, numbness of fingers and Raynaud's phenomenon in female students were 20.9%, 29.5% and 4.6%, respectively, which are 2-3 times higher than those in male adults. 2. The prevalence of Raynaud's phenomenon in female students aged 20-24 yr was equal to that of female adults aged 30-39. It was higher than that of those aged 18-19, 40-49 and 50-59. The prevalence of Raynaud's phenomenon in males did not show any difference by age group. 3. There was no occupational specificity in the prevalence of Raynaud's phenomenon, but the prevalences in male sales workers and in female professional and technical workers were higher than in other groups.