Type 2 diabetes and three calpain-10 gene polymorphisms in Samoans: no evidence of association.
Although genomewide scans have identified several potential chromosomal susceptibility regions in several human populations, finding a causative gene for type 2 diabetes has remained elusive. Others have reported a novel gene, calpain-10 (CAPN10), located in a previously identified region on chromosome 2q37.3, as a putative susceptibility gene for type 2 diabetes. Three single-nucleotide polymorphisms (SNPs) (UCSNP43, UCSNP19, and UCSNP63) were shown to be involved in increased risk of the disease among Mexican Americans. We have tested the association of these three SNPs with type 2 diabetes among the Samoans of Polynesia, who have a very high prevalence of the disease. In the U.S. territory of American Samoa, prevalence is 25% and 15% in men and women, respectively, whereas, in the independent nation of Samoa, prevalence is 3% and 5% in men and women, respectively. In our study sample, which consisted of 172 unrelated affected case subjects and 96 control subjects, we failed to detect any association between case subjects and control subjects in allele frequencies, haplotype frequencies, or haplotype combinations of UCSNP43, -19, and -63. Also, our data showed no evidence of linkage, among 201 affected sib pairs, in the region of chromosome 2 that contains these SNPs. Three plausible scenarios could explain these observations. (1) CAPN10 is a susceptibility gene only in particular ethnic groups; (2) our study lacks power to detect the effects of CAPN10 polymorphisms (but our sample size is comparable to that of earlier reports); or (3) the underlying biological mechanism is too complex and requires further research. (+info)
Culturally based interventions for substance use and child abuse among native Hawaiians.
OBJECTIVE: This article presents an overview of child abuse among culturally diverse populations in Hawaii, substance use among culturally diverse students in Hawaii, and culturally based interventions for preventing child abuse and substance abuse in Native Hawaiian families. OBSERVATIONS: Native Hawaiians accounted for the largest number of cases of child abuse and neglect in Hawaii between 1996 and 1998. Alcohol and other drugs have increasingly been linked with child maltreatment. Native Hawaiian youths report the highest rate of substance use in Hawaii. Cultural factors such as spirituality, family, and cultural identification and pride are important in interventions with Native Hawaiians. CONCLUSION: Human services should continue to emphasize interventions that integrate "mainstream" and cultural-specific approaches. (+info)
Persistence of an extreme sex-ratio bias in a natural population.
The sex ratio is a key parameter in the evolution and ecology of a species. Selfish genetic elements that bias the sex ratio of affected individuals are well known and characterized, but their effect on populations has been considered limited, because either the element does not achieve high prevalence or the host rapidly evolves resistance to the distorting element, reducing its prevalence. We tested whether the host necessarily prevails by using a butterfly system where records from the early part of the 20th century reported extreme sex-ratio bias in nature. We reexamined this population and found the bias was present today, 400 generations after the original record, with a population sex ratio of 100 females per male. The sex-ratio bias was associated with the presence of a heritable male-killing Wolbachia infection in 99% of adult females, against which the host butterfly has failed to evolve resistance. The resultant dearth of males causes an average 57% reduction in the reproductive output of adult females. Persistence of the population despite the very high frequency of the sex-ratio distorter appears to be associated with the ability of males to mate >50 times in their life combined with a high intrinsic rate of increase of the species. (+info)
Distribution of genome-wide linkage disequilibrium based on microsatellite loci in the Samoan population.
Whole genome-wide scanning for susceptibility loci based on linkage disequilibrium (LD) has been proposed as a powerful strategy for mapping common complex diseases, especially in isolated populations. We recruited 389 individuals from 175 families in the US territory of American Samoa, and 96 unrelated individuals from American Samoa and the independent country of Samoa in order to examine background LD by using a 10 centimorgan (cM) map containing 381 autosomal and 18 X-linked microsatellite markers. We tested the relationship between LD and recombination fraction by fitting a regression model. We estimated a slope of -0.021 (SE 0.00354; p<0.0001). Based on our results, LD in the Samoan population decays steadily as the recombination fraction between autosomal markers increases. The patterns of LD observed in the Samoan population are quite similar to those previously observed in Palau but markedly contrast with those observed in a non-isolated Caucasian sample, where there is essentially no marker-to-marker LD. Our analyses support the hypothesis of a recent bottleneck, which is consistent with the known demographic history of the Samoan population. Furthermore, population substructure tests support the hypothesis that self-identified Samoans represent one homogenous genetic population. (+info)
1999-2001 Cancer mortality rates for Asian and Pacific Islander ethnic groups with comparisons to their 1988-1992 rates.
We report upper and lower boundary estimates of the 1999-2001 site-specific cancer mortality rates for Asian Indians, Chinese, Filipinos, Koreans, Vietnamese, Native Hawaiians, and Samoans. These rates are for the seven states (California, Hawaii, Illinois, New Jersey, New York, Texas, and Washington) that officially record mortality data for these ethnicities. The rates are based on the 2000 Census, which reports two population counts as follows: persons who identify themselves as belonging to a single ethnic group (which forms the basis for an upper boundary estimate of the rates) and persons who identify themselves as belonging to a single ethnic group or to multiple groups that include the single ethnic group (which forms the basis for a lower boundary estimate for the rates). The top five cancers for each Asian and Pacific Islander ethnic group by gender are reported. In addition, the 1988-1992 cancer mortality rates based on the 1990 Census for Chinese, Filipino, Japanese, and Native Hawaiians are determined. Their 1999-2001 and 1988-1992 rates are compared. (+info)
Hepatitis C virus infection in Samoa and American Samoa.
Little is known about the prevalence of hepatitis C virus (HCV) in Pacific islands. In this study, serum specimens collected in 1985 and 2002 among the general populations of Samoa and American Samoa were tested for antibody to HCV by a third-generation enzyme immunoassay and a recombinant immunoblot assay. Of the 3,466 specimens tested, 8 (0.2%; 95% confidence interval = 0.07-0.4%) were positive for antibody to HCV. Prevalence did not vary by location or demographic characteristic. Thus, HCV is present in the Samoas but at a low prevalence. (+info)
Vailulu'u Seamount, Samoa: Life and death on an active submarine volcano.
Submersible exploration of the Samoan hotspot revealed a new, 300-m-tall, volcanic cone, named Nafanua, in the summit crater of Vailulu'u seamount. Nafanua grew from the 1,000-m-deep crater floor in <4 years and could reach the sea surface within decades. Vents fill Vailulu'u crater with a thick suspension of particulates and apparently toxic fluids that mix with seawater entering from the crater breaches. Low-temperature vents form Fe oxide chimneys in many locations and up to 1-m-thick layers of hydrothermal Fe floc on Nafanua. High-temperature (81 degrees C) hydrothermal vents in the northern moat (945-m water depth) produce acidic fluids (pH 2.7) with rising droplets of (probably) liquid CO(2). The Nafanua summit vent area is inhabited by a thriving population of eels (Dysommina rugosa) that feed on midwater shrimp probably concentrated by anticyclonic currents at the volcano summit and rim. The moat and crater floor around the new volcano are littered with dead metazoans that apparently died from exposure to hydrothermal emissions. Acid-tolerant polychaetes (Polynoidae) live in this environment, apparently feeding on bacteria from decaying fish carcasses. Vailulu'u is an unpredictable and very active underwater volcano presenting a potential long-term volcanic hazard. Although eels thrive in hydrothermal vents at the summit of Nafanua, venting elsewhere in the crater causes mass mortality. Paradoxically, the same anticyclonic currents that deliver food to the eels may also concentrate a wide variety of nektonic animals in a death trap of toxic hydrothermal fluids. (+info)
Body image differences among Malay, Samoan, and Australian women.
Comparisons of body attitudes and associated behaviours were undertaken using Malay, Samoan, and Australian female students. The general goal of the research was to determine the degree to which the observed pattern of attitudes and behaviours was attributable to culture. The specific analyses comprised an examination of group differences using standard measures that included the Body Attitudes Questionnaire, the Three-Factor Eating Questionnaire and detailed questions concerning the use of diet and exercise as weight control strategies. The main findings concerned a number of cultural differences, particularly in relation to diet and exercise, that were evident even with the effect of body mass index held constant. These results are interpreted in terms of the efficacy of entrenched cultural beliefs in protecting against introduced, more dominant, cultural values. The Australian sample exhibited the most negative body image, although there was some evidence that Malays and Samoans were influenced by Western ideals of weight and shape. It is proposed that to fully understand the differential meaning of negative body image across cultures and the potential impact of westernisation, both within-group and between-group differences in body size need to be acknowledged. (+info)