The histocompatibility complex (MHC) is one of the gene systems that influence aging. The HLA antigens in humans, particularly those associated with the HLA-D region, are closely related to autoimmune diseases, cancer, immune responsiveness, and other malignancies. However, it is not yet known whether such a relationship exists between HLA and longevity. Although the advantage of HLA heterozygosity and the disadvantage of AI-B8 haplotype for Caucasian women have been suggested earlier. Only 11 Japanese subjects and 16 Caucasians have been investigated for the distribution of HLA antigens among centenarians so far. The Okinawa islands, which are the southernmost part of Japan, are known for the longevity of their populations. In 1980, the average life expectancy was 74.52 years for men and 81.72 years for women, and according to Ministry of Health and Welfare data, there were about 5 centenarians per 100,000 of the population in 1984.

The phenotypes in 82 centenarians and 20 nonagenarians in Okinawa, Japan were compared with those in other healthy adults in various age brackets. Subjects aged over 90 had an extremely low frequency of HLA-DRw9 and an increased frequency of DR1. In this age group, the relative risk of HLA-DRw9 was 5.2, and the corrected p-value (for the number of antigens) was 0.0001; those for HLA-DR1 were 13.3 and 0.0367, respectively. Since a high frequency of DRw9 and a low frequency of DR1 are associated with autoimmune or immune deficiency diseases, genetic protection against these disorders may contribute to longevity.

Since 1979, blood samples collected from 82 strictly verified centenarians and 20 nonagenarians who lived on the Okinawa islands were investigated to compare HLA-A, B, C, DR, and DQ antigen phenotypes with those of average, normal adults of the same geographic region. In this report, we present data that suggests that some primary genetic factors, including MHC region genes, are associated with human longevity.

The subjects included 82 centenarians (18 males and 64 females) aged 100 to 106 years (average 101.1 years), 20 nonagenarians (4 males and 16 females) aged 90 to 99 years (average 96.5 years), and 159 healthy adults (78 males and 81 females) aged 18 to 85 years (average 58.1 years). Only those found to be in good general health after clinical examination were included in the survey.

It is very rare for humans to live beyond 100 years, and environmental factors such as lifestyle, diet, and climate would have a strong influence on longevity. Since long life runs in families, genetic factors probably also contribute to longevity. The age given by centenarians and nonagenarians was checked against family registers, age of subject at the time of major events such as birth records, subjects' personal recollections, and family lineage. In cases of even the slightest doubt, subjects were excluded from the survey.

The clear-cut relation between maximum lifespan in mice and the H-2 system suggests that major genetic factors such as the MHC region genes are associated with human longevity.

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Monder C, Shackleton CHL, Bradlow HL, et al. The syndrome of apparent mineralocorticoid excess: Its association with beta-dehydrogenase and beta-reductase deficiency and some consequences for corticosteroid metabolism- J Clin Endocrinol Metab; :The text seems to be a mix of different sections, including references and data analysis tables. It is difficult to understand the original intent without more context. However, there are some clear issues with spelling, grammar, and formatting throughout the text. Here is an attempt to process the text:

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Gerkins VR, Ting A, Menck HT, et al. HL-A heterozygosity as a genetic marker for long-term survival. J Natl Cancer Inst;  : - 

Yasuda N, Tsuji K, Itakura K. HLA heterozygosity in children and old people. J Exp Clin Med;  : -