Individuals living in the industrialized countries are exposed extensively to air pollutants and chemicals that cause DNA mutations, cancer and birth defect. Recent studies have suggeted that inherited differences in metabolic capacity may play a primary role in susceptibility to environmentally induced cancers. In this respect, polymorphic alleles of Glutathione S-Transferase (GSTM1) which is important in the detoxication of several carcinogens were analyzed the 104 controls and 172 patients with lung cancer in Sheng-Yen district of China. The frequencies of GSTM1 gene deletion was significantly higher in the patients with lung cancer than in control (p<0.01). GSTM1 gene deletion was found to be higher risk factor in small cell carcinoma than in squamous cell carcinoma and adenocarcinoma.
In our recent studies, allelic polymorphism of aldehyde dehydrogenase 2 (ALDH2) have revealed that the ALDH2^*2 frequency was less common in alcoholics compared with healthy controls. This observation indicates that individuals possessing ALDH2^*2 may refrain from excessive drinking due to averse reaction caused by a raise of blood acetaldehyde level. In this sense, ALDH2^*2 plays a protective role against alcoholism. This mutant was found only in Mongoloid population groups. In our country, the higher frequency of the mutant was found in Kinki- and Chubu-district (28.4% and 27.2%). On the contrary, Kyusyu- and Tohoku-district were found to be lower (20.9% and 18.8%). These data suggested a possible existence of gene-cline for the ALDH2^*2 allele.
Recently, Cloninger et al. (1993) proposed that the heritable human personality traits consist of four distinct domains of temperaments designated as Novelty Seeking (NS). Harm Avoidance (HA), Reward Dependence (RD) and Persistence (P) by the experimental data to be based on neurochemical reaction to various substrates. Each subcomponent is mediated by genetic variability of central nerve system for dopamine, serotonin and noradrenalin. In our study, genetic variation in promoter and the coding regions of the CCK gene were analyzed among healthy volunteers to find genetic polymorphism by using PCR, SSCP and Sequencing techniques. We found a frequent mutation at nucleotide position- 45 C to T involved in core sequence of Sp1 binding cis-element of the promoter region. TPQ data were analyzed separately in CC, CT and TT genotypes. Analysis of variance revealed that the group of subjects (CT and TT) with the -45 T exhibit significantly elevated HA scores in comparison to subject (CC) lacking the -45 T. The blood concentration of CCK peptides was significantly lower in the subjects with CT and TT compared with CC. Our data indicated that the nucleotide replacement at -45 C to T in promoter may affect the production of CCK peptide, and this might influence to HA scores.

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Demographic analysis has been one of the central foci in studies of both health sciences and authropology, particularly those from an ecological standpoint. Demographic transition, i.e., a process from high fertility and high mortality to high fertility and low mortality and then to low fertility and low mortality, took place first in West European countries from the middle 18th century to the early 20th century, and the similar phenomenon has progressed in developing countries with marked inter-regional differences in both onset time and pace. The analysis of crude birth and death rates in 1973, 1983 and 1993 by regions revealed that death rate has continuously declined in any regions but decrease in fertility rate from 1983 to 1993 was lower than that from 1973 to 1983 in West Asia and Southeast Asia, suggesting that the lowered mortality and less-lowered fertility combined have resulted in markedly high population increase. A genealogical-demographic analysis for the Gidra-speaking population in Papua New Guinea, among whom the author has repeated ecological field research, clarified manifest decrease in mortality and manifest increase in fertility in the recent decades in accordance with modernization, represented by medical services such as immunization to children. Taking into account the general pattern that mortality directly reflects health status but fertility is largely determined by married couple's decision-makings by means of contraceptive practice, the interrelationships between fertility and mortality changes in anthropological populations should be further studied to provide significant information for understanding global population issues.

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Skeletal aging can be modified by many factors such as hormonal insufficiency, long-term mechanical loading activity, occupational history and environmental conditions. The feature of skeletal aging could be basically classified into two categories; i.e., one is sclerotic and proliferative bone changes represented by osteoarthritis (OA) and another is lytic or softening bone changes represented by osteoporosis (OP). OA characterized by narrowing joint space, osteophyte, eburnation and cyst, seems to be predominant in the past. Particularly, spondylosis deformans in the vertebral column (SD), one of the regional form of OA, must be very prevalent in the ancient because of hard physical activity which demands site-specific mechanical loading to the vertebrae. In contrast osteoporosis characterized by low bone mass and microarchitectural detorioration of bone tissue resulted in a consequence increase of bone fragility and susceptibility to fracture, is evidently prevalent among today's Japanese people. In the present study, using the skeletal sample of modern Japanese who had macerated by almost the same manner during anatomical dissection in the Meiji period, the authors measured bone mineral density (BMD) in the trabecular region in the center of the vertebral body from the second to the fourth lumbar vertebrae by DXA. At the same time, the degree of osteophyte by SD in the lumbar were recorded to evaluate the relationship between OP and SD in the same vertebral body. As the result, there was clear decline of BMD with aging, which was independent of coexistence of SD. The results indicate that, if preserved condition is in the same, it is possible to make a diagnosis of osteopenia/osteoporosis even in the macerated or excavated skeletal samples.

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Morphologies of the DEJ which might have phylogenetically primitive characters are important for understanding the phylogeny of the human teeth. Morphological traits on the outer enamel surface (OES) can be observed clearly on the dentino-enamel junction (DEJ) as a distinct ridge or a process even if they are not distinct on the OES. We observed ten characters on the OES and DEJ of lower second deciduous molars (m₂), and examined significant differences of these frequencies between the DEJ and OES. We also compared the frequencies of occurrence with the lower permanent first molar (M₁) and searched for morphological relationship among four surfaces by distance analysis.
The following results were obtained;
1. On the buccal surface of m₂, frequencies of occurrence of characters on the DEJ were almost higher than on the OES. And on the DEJ, frequencies of occurrence of the buccal marginal ridge (mesial) and protostylid of the m₂ were higher than in M₁.
2. On the occlusal surface of the DEJ of m₂, frequency of occurrence of metaconid distal accessory tubercle forming the seventh cusp was higher than on the OES. Frequencies of occurrence of the middle trigonid crest, distal trigonid crest, sixth cusp, seventh cusp and mesial accessory tubercle of the m₂ were higher than in M₁.
3. The distance analysis indicated that there was a strong resemblance between the DEJ of m₂ and of M₁, and between the OES of m₂ and of M₁. This study suggested that the frequencies of primitive crown characters were retained most in the DEJ of the m₂ among four surfaces in the m₂-M₁ series.

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