Body mass index and obesity-related metabolic disorders in Taiwanese and US whites and blacks: implications for definitions of overweight and obesity for Asians

BACKGROUND

Recommendations based on scanty data have been made to lower the body mass index (BMI; in kg/m(2)) cutoff for obesity in Asians.

OBJECTIVE

The goal was to compare relations between BMI and metabolic comorbidity among Asians and US whites and blacks.

METHODS

We compared the prevalence rate, sensitivity, specificity, predictive values, and impact fraction of comorbidities at each BMI level and the BMI-comorbidity relations across ethnic groups by using data from the third National Health and Nutrition Examination Survey and the Nutrition and Health Survey in Taiwan (1993-1996).

RESULTS

For most BMI values, the prevalences of hypertension, diabetes, and hyperuricemia were higher for Taiwanese than for US whites. In addition, increments of BMI corresponded to higher odds ratios in Taiwanese than in US whites for hypertriglyceridemia (P = 0.01) and hypertension (P = 0.075). BMI-comorbidity relations were stronger in Taiwanese than in US blacks for all comorbidities studied. BMIs of 22.5, 26, and 27.5 were the cutoffs with the highest sum of positive and negative predictive value for Taiwanese, US white, and US black men, respectively. The same order was observed for women. For BMIs >27, >85% of Taiwanese, 66% of whites, and 55% of blacks had at least one of the studied comorbidities. However, a cutoff close to the median of the studied population was often found by maximizing sensitivity and specificity. Reducing BMI from >25 to <25 in persons in the United States could eliminate 13% of the obesity comorbidity studied. The corresponding cutoff in Taiwan is slightly <24.

CONCLUSION

These data suggest a possible need to set lower BMI cutoffs for Asians, but where to draw the line is a complex issue.

Spinocerebellar ataxia type 2 with parkinsonism in ethnic Chinese

OBJECTIVE

To describe the clinical and molecular genetic analysis of a large family of northern Chinese descent with a mutation at the SCA2 locus causing carbidopa-levodopa-responsive parkinsonism.

BACKGROUND

Most causes of parkinsonism remain unknown. However, molecular genetic analysis of families with parkinsonism has recently identified five distinct loci and pathogenic mutations in four of those. Additionally, some of the spinocerebellar ataxia syndromes (SCA), particularly Machado-Joseph syndrome (SCA3), are known to cause parkinsonism. Spinocerebellar ataxia type 2 (SCA2) has not previously been described as causing a typical dopamine-responsive asymmetric PD phenotype.

METHODS

A large family was evaluated clinically and molecularly for apparent autosomal dominant parkinsonism.

RESULTS

The phenotype includes presentation consistent with typical dopamine-responsive parkinsonism. Other presentations in this family include a parkinsonism/ataxia phenotype, which is classic for SCA2 and parkinsonism, resembling progressive supranuclear palsy.

CONCLUSIONS

Patients presenting with a family history of parkinsonism, including familial progressive supranuclear palsy and PD, should be tested for the spinocerebellar ataxia type 2 expansion.

Validation of the Brief Pain Inventory in a Taiwanese population

Assessment of pain in cancer patients is very important to all health care professionals. This paper describes the development of a Taiwanese version of the Brief Pain Inventory (BPI-T) and discusses its psychometric properties in Taiwan. The BPI-T was developed from the original BPI using back-translation and committee review. A total of 534 cytologically or pathologically diagnosed cancer patients in three medical centers in Taiwan were interviewed between July 1992 and October 1997. The intraclass correlation coefficient for the test-retest reliability was 0.79 for the pain severity scale and 0.81 for the pain interference scale. The explained variance for the within-scale factor analyses was larger than 60% in both scales. The coefficient alpha for the internal reliability was 0.81 for the severity scale and 0.89 for the interference scale. Confirmatory factor analysis of the BPI-T clearly identified the same two scales (severity and interference scales) in the 299 adult patients (age between 20-64) with high education (education years > 9) or patients at an early stage of disease. However, in the 235 nonadult patients with distant metastasis or low education patients with distant metastasis, the "most severe pain" item loaded more to the interference scale than the severity scale. Convergent validity of the pain severity was demonstrated by significant correlations with stage of disease (National Cancer Institute's Surveillance, Epidemiology, and End Results Program [SEER]), performance status (Eastern Cooperative Oncology Group [ECOG]), and pain interference. In conclusion, interviewer-administered BPI-T was a reliable instrument for cancer pain severity and its interference in Taiwan. Additionally, it was a valid instrument on adult cancer patients with high education or patients at an early stage of disease.

Understandings of death and dying for people of Chinese origin

This article introduces the primary beliefs about ancestor worship, Taoism, Confucianism, Buddhism and traditional Chinese medicine that have influenced Chinese people for thousands of years, particularly in relation to death and dying. These cultures and traditions remain important for Chinese people wherever they live. Over a long period, Chinese people have integrated these philosophies and religions to form the basis of their culture and traditions. Although they agree that death is a natural part of the life span, a unique belief about death and dying has emerged among the Chinese from this integration. From this, the people find a significant definition of death and dying.

Traces of archaic mitochondrial lineages persist in Austronesian-speaking Formosan populations

Genetic affinities between aboriginal Taiwanese and populations from Oceania and Southeast Asia have previously been explored through analyses of mitochondrial DNA (mtDNA), Y chromosomal DNA, and human leukocyte antigen loci. Recent genetic studies have supported the "slow boat" and "entangled bank" models according to which the Polynesian migration can be seen as an expansion from Melanesia without any major direct genetic thread leading back to its initiation from Taiwan. We assessed mtDNA variation in 640 individuals from nine tribes of the central mountain ranges and east coast regions of Taiwan. In contrast to the Han populations, the tribes showed a low frequency of haplogroups D4 and G, and an absence of haplogroups A, C, Z, M9, and M10. Also, more than 85% of the maternal lineages were nested within haplogroups B4, B5a, F1a, F3b, E, and M7. Although indicating a common origin of the populations of insular Southeast Asia and Oceania, most mtDNA lineages in Taiwanese aboriginal populations are grouped separately from those found in China and the Taiwan general (Han) population, suggesting a prevalence in the Taiwanese aboriginal gene pool of its initial late Pleistocene settlers. Interestingly, from complete mtDNA sequencing information, most B4a lineages were associated with three coding region substitutions, defining a new subclade, B4a1a, that endorses the origin of Polynesian migration from Taiwan. Coalescence times of B4a1a were 13.2 +/- 3.8 thousand years (or 9.3 +/- 2.5 thousand years in Papuans and Polynesians). Considering the lack of a common specific Y chromosomal element shared by the Taiwanese aboriginals and Polynesians, the mtDNA evidence provided here is also consistent with the suggestion that the proto-Oceanic societies would have been mainly matrilocal.

Reliability and validity of the Chinese version of the Job Content Questionnaire in Taiwanese workers

The reliability and validity of four selected scales--namely, job control, psychological demands, supervisor support, and coworker support--from the Chinese Version of the Job Content Questionnaire (C-JCL) were studied in 551 male and 648 female workers in Taiwan. Cronbach's alpha coefficients for job control, supervisor support, and coworker support were all above.80. Whereas it was.55 for psychological demands, indicating insufficient internal consistency for this subscale. Participants responded to questionnaire items relatively consistently over a 3-month period. Exploratory factor analyses disclosed 4 empirical factors, which corresponded closely with theoretical constructs of the JCL. As predicted by the model, lowest levels of job satisfaction were found in workers in "iso-strain" category (i.e., high demands combined with low control and low social support). These findings indicated that the C-JCL is reliable and valid for assessing psychosocial work conditions among Taiwanese workers, although further improvement is needed for the psychological demands subscale.

Risk of hepatocellular carcinoma and habits of alcohol drinking, betel quid chewing and cigarette smoking: a cohort of 2416 HBsAg-seropositive and 9421 HBsAg-seronegative male residents in Taiwan

OBJECTIVES

Hepatitis B virus (HBV) is a major cause of hepatocellular carcinoma (HCC) in the world. The specific aim of this study is to assess the associations between the risk of HCC and habits of alcohol drinking, betel quid chewing and cigarette smoking among subjects with and without chronic HBV infection.

METHODS

A total of 11,837 male residents in Taiwan were recruited in this community-based cohort study. Hepatitis B surface antigen (HBsAg) and antibody against hepatitis C virus (anti-HCV) in serum were determined by enzyme immunoassay, and the habits of alcohol drinking, betel quid chewing and cigarette smoking were collected through standardized personal interview according to a structured questionnaire. During the follow-up period of 91,885 person-years, 115 incident HCC cases were identified through data linkage with national cancer registry profile. The relative risk (RR) of developing HCC for habits of various substance use and chronic HBV infection were estimated by Cox's proportional hazards regression analyses.

RESULTS

Significantly increased HCC risk was observed for seropositives of HBsAg or anti-HCV, alcohol drinkers, betel quid chewers and cigarette smokers. There was a significant dose-response relationship between the risk of HCC and the number of habits of substance use. The highest multivariate-adjusted HCC risk was observed among HBsAg-seropositive substance users (RRs: 17.9-26.9), followed by HBsAg-seropositive non-users (RRs: 13.1-19.2), HBsAg-seronegative substance users (RRs: 1.6-2.7) and HBsAg-seronegative non-users (referent with RR = 1). The multivariate-adjusted relative HCC risks for habits of use of various substances were more profound among HBsAg-seronegatives than HBsAg-seropositive ones.

CONCLUSION

Habitual alcohol drinking, betel quid chewing and cigarette smoking are associated with an increased risk of HCC. Abstinence from substance use is important for the prevention of HCC in areas where chronic HBV infection is endemic.

Melanesian origin of Polynesian Y chromosomes

BACKGROUND

Two competing hypotheses for the origins of Polynesians are the 'express-train' model, which supposes a recent and rapid expansion of Polynesian ancestors from Asia/Taiwan via coastal and island Melanesia, and the 'entangled-bank' model, which supposes a long history of cultural and genetic interactions among Southeast Asians, Melanesians and Polynesians. Most genetic data, especially analyses of mitochondrial DNA (mtDNA) variation, support the express-train model, as does linguistic and archaeological evidence. Here, we used Y-chromosome polymorphisms to investigate the origins of Polynesians.

RESULTS

We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia.

CONCLUSIONS

All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the 'slow-boat' model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

Two signatures of implicit intergroup attitudes: developmental invariance and early enculturation

Long traditions in the social sciences have emphasized the gradual internalization of intergroup attitudes and the putatively more basic tendency to prefer the groups to which one belongs. In four experiments (N = 883) spanning two cultures and two status groups within one of those cultures, we obtained new evidence that implicit intergroup attitudes emerge in young children in a form indistinguishable from adult attitudes. Strikingly, this invariance from childhood to adulthood holds for members of socially dominant majorities, who consistently favor their in-group, as well as for members of a disadvantaged minority, who, from the early moments of race-based categorization, do not show a preference for their in-group. Far from requiring a protracted period of internalization, implicit intergroup attitudes are characterized by early enculturation and developmental invariance.

A longitudinal study of cognition change during early menopausal transition in a rural community

OBJECTIVE

To characterize changes in cognition that occur during the hormonal transitions of menopause.

METHOD

We conducted a longitudinal population-based study in Kinmen, Taiwan, recruiting all women age 40-54 years who were premenopausal and without a history of hormone replacement therapy (HRT) or hysterectomy. The cognitive measures used to assess function included the Auditory-Verbal Learning Test, visual memory, verbal fluency, Trail Making Test and digit span.

RESULTS

A total of 694 eligible women participated in the baseline study, and 573 women (83%) completed follow-up 18 months later. After excluding 78 women who received hysterectomy or HRT, the final sample was composed of 495 subjects, of whom 114 (23%) progressed to perimenopause during follow-up. Women who remained premenopausal were younger than those who became perimenopausal (44.7 +/- 2.3 years versus 47.1 +/- 3.0 years, p < 0.01). All follow-up cognitive scores in women who entered perimenopause were slightly better than baseline measures except for Rey Auditory-Verbal Learning Test, which decreased by 0.23 (S.D. = 2.9, p = 0.3). At follow-up, cognitive function except for verbal fluency did not differ significantly between women who stayed premenopausal and those became perimenopausal after controlling for age, education, and baseline cognitive scores. Women who entered perimenopause have an average of 1.3 items (S.D. = 0.4) less in verbal fluency measures as compared with their premenopausal peers at the follow-up period.

CONCLUSIONS

The menopausal transition might not accompany significant cognitive decline except for verbal fluency.

Subtypes of ischemic stroke. A hospital-based stroke registry in Taiwan (SCAN-IV)

BACKGROUND AND PURPOSE

To better understand the clinical pattern and further elucidate the risk factors and outcome in different subtypes of cerebral infarction (CI) of the Chinese in Taiwan, we analyzed the National Taiwan University Hospital Stroke Registry in 1995 and performed an ethnic comparison with similar data banks.

METHODS

From the National Taiwan University Hospital Stroke Registry in 1995, 676 patients (383 men and 293 women; mean age, 64.9 years; SD, 13.8 years; range, 1 to 98 years) with CI were recruited for this analysis. CI was classified into five subtypes based on clinical manifestations, ultrasonographic studies, and neuroimaging findings: large-artery atherosclerosis, lacunae, cardioembolism, other less common determined causes, and undetermined cause. Vascular risk factors, extracranial carotid artery atherosclerosis, and 30-day case-fatality rates were investigated in each subtype of CI.

RESULTS

Of all CI patients, 17%, 29%, 20%, 6%, and 29% were classified as large-artery atherosclerosis, lacunae, cardioembolism, other determined causes, and undetermined cause subtypes, respectively. The present results were compared with those from eight similar Western stroke registries. The relative incidence of lacunar CI in Chinese patients was more common, but large-artery atherosclerotic CI was less common than in whites. Hypertension was frequently seen in CI patients, especially in those with lacunae (85%) and large-artery atherosclerosis (69%). Patients with cardioembolism had a higher percentage of atrial fibrillation (69%), left ventricular hypertrophy, and ischemic heart disease than the other patients. Patients with large-artery atherosclerosis had more vascular risk factors, such as hypertension, diabetes mellitus, smoking, and carotid stenosis. Cardioembolic patients had higher case-fatality rates than other CI patients. Of the cardioembolic patients, 17.3% and 21.8% died within 30 days and during hospitalization, respectively.

CONCLUSIONS

The proportion of CI subtypes varied in different stroke registries. This may be partly due to applied classification criteria and racial-ethnic differences. Awareness of the risk factors and outcome in each subtype of stroke may afford further insights into the surveillance and treatment of cerebrovascular disease.

Long contiguous stretches of homozygosity in the human genome

Single nucleotide polymorphisms (SNPs) are the most common sequence variation in the human genome; they have been successfully used in mapping disease genes and more recently in studying population genetics and cancer genetics. In a population-based association study using high-density oligonucleotide arrays for whole-genome SNP genotyping, we discovered that in the genomes of unrelated Han Chinese, 34 out of 515 (6.6%) individuals contained long contiguous stretches of homozygosity (LCSHs), ranging in the size from 2.94 to 26.27 Mbp (10.22+/-5.95 Mbp). Four out of four (100%) Taiwan aborigines also demonstrated this genetic characteristic. The number of LCSH regions increased markedly in the offspring of consanguineous marriages. LCSH was also detected in Caucasian samples (11/42; 26.2%) and African American samples (2/42; 4.76%). A total of 26 LCSH regions were recurrently detected among Han Chinese, Taiwan aborigines, and Caucasians. DNA copy number determination by hybridization intensity analysis and real-time quantitative PCR (qPCR) excluded deletion as the cause of LCSH. Our results suggest that LCSHs are common in the human genome of the outbred population and this genetic characteristic could have a significant impact on population genetics and disease gene studies.

Glucocerebrosidase mutations in Chinese subjects from Taiwan with sporadic Parkinson disease

BACKGROUND

An association between glucocerebrosidase, the enzyme deficient in Gaucher disease, and the synucleinopathies has been suggested both by the development of parkinsonism in Gaucher probands and carriers, as well as by the presence of mutations in the gene for glucocerebrosidase (GBA) in different series of subjects with synucleinopathies. In this study, an open access Parkinson repository was used to establish the incidence of GBA alterations in a different ethnic cohort with sporadic Parkinson disease (PD).

METHODS

The glucocerebrosidase gene was sequenced in samples collected from 92 Chinese Parkinson disease patients from Taiwan along with 92 clinically screened controls, matched for age and ethnicity.

FINDINGS

The frequency of GBA mutations among the Chinese PD probands was 4.3%, in contrast to 1.1% in Chinese controls. Mutant alleles identified included two known mutations, L444P and D409H, and two novel mutations, L174P and Q497R.

INTERPRETATION

These results, ascertained in subjects from Taiwan collected in a standardized and clinically rigorous open access Parkinson disease repository and screened by direct sequencing of GBA, demonstrate that GBA mutations are also encountered in Chinese subjects with sporadic PD at a higher frequency than many other known PD genes. The study demonstrates that the association of GBA mutations with the development of parkinsonian pathology is not related to ethnic origin.

Male body image in Taiwan versus the West: Yanggang Zhiqi meets the Adonis complex

OBJECTIVE

Body image disorders appear to be more prevalent in Western than non-Western men. Previous studies by the authors have shown that young Western men display unrealistic body ideals and that Western advertising seems to place an increasing value on the male body. The authors hypothesized that Taiwanese men would exhibit less dissatisfaction with their bodies than Western men and that Taiwanese advertising would place less value on the male body than Western media.

METHOD

The authors administered a computerized test of body image to 55 heterosexual men in Taiwan and compared the results to those previously obtained in an identical study in the United States and Europe. Second, they counted the number of undressed male and female models in American versus Taiwanese women's magazine advertisements.

RESULTS

In the body image study, the Taiwanese men exhibited significantly less body dissatisfaction than their Western counterparts. In the magazine study, American magazine advertisements portrayed undressed Western men frequently, but Taiwanese magazines portrayed undressed Asian men rarely.

CONCLUSIONS

Taiwan appears less preoccupied with male body image than Western societies. This difference may reflect 1) Western traditions emphasizing muscularity and fitness as a measure of masculinity, 2) increasing exposure of Western men to muscular male bodies in media images, and 3) greater decline in traditional male roles in the West, leading to greater emphasis on the body as a measure of masculinity. These factors may explain why body dysmorphic disorder and anabolic steroid abuse are more serious problems in the West than in Taiwan.

Culture and Social Comparison Seeking: The Role of Self-Motives

Three studies examined the relation between cultural background and social comparison seeking. Compared to European Canadians, Asian Canadians sought more social comparisons, particularly those that were upward (Study 1), more social comparisons after failure (Study 2), and more social comparisons after failure when the opportunity for self-improvement was made salient (Study 3). Taken together, these data spotlight Asian Canadians’ interest in social comparisons that allow for self-improvement.

Perceived risk and help-seeking behavior for breast cancer. A Chinese-American perspective

Delay in the diagnosis and treatment of breast cancer diminishes a woman's chance of survival. How do women decide whether and when to seek an evaluation of breast symptoms that may signal breast cancer? Prior studies of African-American, white, and Latino women have described a number of critical factors associated with making the judgment to delay, but at this writing, there have been no studies factors influencing Chinese-American women. By means of focus group methods in English, Mandarin, and Cantonese, a sample of 45, predominantly first-generation Chinese-American women explained their understanding of breast cancer risk and their likelihood of delaying versus seeking evaluation of self-discovered breast symptoms. There was much congruence with the ideas of other American women despite the differing cultural heritage. Unique to these Chinese Americans was a sense of invulnerability to breast cancer, a linking of cancer to tragic luck, and the predominant likelihood of delay. To preserve modesty and to conserve wealth and time, many study participants favored using Chinese medicine and delaying Western therapies. This study suggests ways by which health care providers must approach guidelines for breast cancer early detection in this population.

A common genetic factor for Parkinson disease in ethnic Chinese population in Taiwan

BACKGROUND

Parkinson's disease (PD) is the most common neurodegenerative movement disorder, characterized clinically by resting tremor, bradykinesia, postural instability and rigidity. The prevalence of PD is approximately 2% of the population over 65 years of age and 1.7 million PD patients (age > or = 55 years) live in China. Recently, a common LRRK2 variant Gly2385Arg was reported in ethnic Chinese PD population in Taiwan. We analyzed the frequency of this variant in our independent PD case-control population of Han Chinese from Taiwan.

METHODS

305 patients and 176 genetically unrelated healthy controls were examined by neurologists and the diagnosis of PD was based on the published criteria. The region of interest was amplified with standard polymerase chain reaction (PCR). PCR fragments then were directly sequenced in both forward and reverse directions. Differences in genotype frequencies between groups were assessed by the X2 test, while X2 analysis was used to test for the Hardy-Weinberg equilibrium.

RESULTS

Of the 305 patients screened we identified 27 (9%) with heterozygous G2385R variant. This mutation was only found in 1 (0.5%) in our healthy control samples (odds ratio = 16.99, 95% CI: 2.29 to 126.21, p = 0.0002). Sequencing of the entire open reading frame of LRRK2 in G2385R carriers revealed no other variants.

CONCLUSION

These data suggest that the G2385R variant contributes significantly to the etiology of PD in ethnic Han Chinese individuals. With consideration of the enormous and expanding aging Chinese population in mainland China and in Taiwan, this variant is probably the most common known genetic factor for PD worldwide.

Culture shapes whether the pursuit of happiness predicts higher or lower well-being

Pursuing happiness can paradoxically impair well-being. Here, the authors propose the potential downsides to pursuing happiness may be specific to individualistic cultures. In collectivistic (vs. individualistic) cultures, pursuing happiness may be more successful because happiness is viewed--and thus pursued--in relatively socially engaged ways. In 4 geographical regions that vary in level of collectivism (United States, Germany, Russia, East Asia), we assessed participants' well-being, motivation to pursue happiness, and to what extent they pursued happiness in socially engaged ways. Motivation to pursue happiness predicted lower well-being in the United States, did not predict well-being in Germany, and predicted higher well-being in Russia and in East Asia. These cultural differences in the link between motivation to pursue happiness and well-being were explained by cultural differences in the socially engaged pursuit of happiness. These findings suggest that culture shapes whether the pursuit of happiness is linked with better or worse well-being, perhaps via how people pursue happiness.

Association of vitamin D receptor gene polymorphism with sporadic breast cancer in Taiwanese patients

PURPOSE

Previous reports have suggested that polymorphism in the vitamin D receptor (VDR) gene is associated with sporadic breast cancer, but there is controversy among different authors and ethnic groups. The purpose of this study was to determine whether polymorphism in the VDR gene might also influence breast cancer risk in Taiwan, a country with a low incidence of breast cancer.

METHODS

Polymorphisms in the end of the VDR gene were genotyped for 34 Taiwanese women with sporadic breast cancer, 46 with benign breast tumors and 169 cancer-free female cohort controls.

RESULTS

The ApaI, TaqI, and BsmI polymorphisms in the 3' end of the VDR gene were associated with breast cancer risk, with a trend for increasing risk with increased numbers of BsmI B alleles and ApaI AA genotypes. When the allele frequencies of BsmI polymorphism were compared among the three populations, a significant difference was observed (chi2 = 13.684, df = 4, p = 0.0084). The OR of the Aa genotype was 0.333 (95% CI = 0.1 14-0.978) and that of the aa genotype was 0.515 (95% CI = 0.190-1.398). These data indicate that the AA genotype may be associated with an increased risk of breast cancer, while the Aa genotype tends to be associated with decreased risk. The TaqI polymorphism was not associated with breast cancer risk in this study.

CONCLUSION

These results suggest that polymorphic variation in or near the 3' end of the VDR gene may influence breast cancer risk in Taiwanese women and justifies further investigation of the role of VDR for sporadic breast cancer in low-incidence areas. These findings also should help when designing targeted therapy.

Fast trains, slow boats, and the ancestry of the Polynesian islanders

The question of the origins of the Polynesians has, for over 200 years, been the subject of adventure science. Since Captain Cook's first speculations on these isolated Pacific islanders, their language affiliations have been seen as an essential clue to the solution. The geographic and numeric centre of gravity of the Austronesian language family is in island Southeast Asia, which was therefore originally seen as their dispersal homeland. However, another view has held sway for 15 years, the 'out of Taiwan' model, popularly known as the 'express train to Polynesia'. This model, based on the combined evidence of archaeology and linguistics, proposes a common origin for all Austronesian-speaking populations, in an expansion of rice agriculturalists from south China/Taiwan beginning around 6,000 years ago. However, it is becoming clear that there is, in fact, little supporting evidence in favour of this view. Alternative models suggest that the ancestors of the Polynesians achieved their maritime skills and horticultural Neolithic somewhere between island Southeast Asia and Melanesia, at an earlier date. Recent advances in human genetics now allow for an independent test of these models, lending support to the latter view rather than the former. Although local gene flow occurring between the bio-geographic regions may have been the means for the dramatic cultural spread out to the Pacific, the immediate genetic substrate for the Polynesian expansion came not from Taiwan, but from east of the Wallace line, probably in Wallacea itself.

Efficacy and safety of levetiracetam (up to 2000 mg/day) in Taiwanese patients with refractory partial seizures: a multicenter, randomized, double-blind, placebo-controlled study

PURPOSE

To assess the efficacy and safety of adjunctive levetiracetam (LEV) therapy in controlling partial-onset seizures refractory to other antiepileptic drugs (AEDs) in a multicenter study in Taiwanese adults.

METHODS

Ninety-four patients aged 16-60 years with refractory partial seizures were randomized to receive LEV (n = 47) or placebo (47) for 14 weeks and composed the intention-to-treat (ITT) population. After the first 2 weeks, LEV patients had their dosage increased from 500 mg twice daily to 1,000 mg twice daily. A 12-week maintenance phase followed, after which patients switched to long-term, open-label LEV therapy or entered a 4-week phase of medication discontinuation.

RESULTS

All patients from the ITT population, except one LEV-treated patient with missing seizure-count data, were included in the primary efficacy analysis. The least square mean of logarithmically transformed weekly partial-seizure frequency was significantly lower in the LEV than in the placebo group (0.813 vs. 1.085; p = 0.001). LEV reduced log-transformed weekly partial-seizure frequency by 23.8% (95% confidence interval, 10.4-35.2%) relative to placebo. Significantly more LEV than placebo patients (43.5% vs. 10.6%) experienced a response of a >or=50% decrease from baseline in weekly frequency of partial seizures [odds ratio, 6.5 (95% CI, 2.2-19.3); p < 0.001]. Adverse events were reported in 34 (72.3%) of 47 LEV-treated patients and 32 (68.1%) of 47 placebo patients. The three most common adverse events in the LEV and placebo groups were somnolence (40.4% and 14.9%), dizziness (14.9% and 8.5%), and headache (10.6% and 8.5%), respectively. Only four patients (three LEV-treated patients and one placebo patient) were withdrawn from the study because of adverse events.

CONCLUSIONS

Adjunctive LEV therapy, <or=1,000 mg twice daily, was significantly more effective than placebo and was generally well tolerated in Taiwanese adults with treatment-resistant partial-onset seizures.

Earliest Recollections of Self and Others in European American and Taiwanese Young Adults

This study examined the age and content of earliest childhood memories of self and others. European American and Taiwanese participants (N = 111) retrieved their earliest memories in response to the cue words self, mother, family, friend, and surroundings. Memory for mother was from an earlier age than memory for self, and memories for mother, family, and friend were more socially oriented in content than memories for self or surroundings. In addition, in response to all cue words, Euro-Americans recalled memories from an earlier age than did Taiwanese. Euro-Americans also had a greater tendency to report memories of specific events and focused more on their own roles and autonomy than did Taiwanese, who more often described routine events and emphasized the roles of others. These findings have important implications for infantile amnesia and the memory-self interplay.

Genome scan of Han Chinese schizophrenia families from Taiwan: confirmation of linkage to 10q22.3

OBJECTIVE

Genome-wide linkage analyses of schizophrenia have identified several regions that may harbor schizophrenia susceptibility genes, but given the complex etiology of the disorder, it is unlikely that all susceptibility regions have been detected. To address this issue, the authors ascertained 606 Han Chinese families comprising 1,234 affected members.

METHOD

Probands with schizophrenia were recruited from six data collection field research centers in Taiwan. Each proband underwent a diagnostic screen with supplemental medical records and a semistructured interview. Following this screen, the authors administered the Mandarin Chinese version of the Diagnostic Interview for Genetic Studies. Best-estimate final diagnoses were made by two board-certified psychiatrists. The genotyping was conducted by the Center for Inherited Disease Research, with 386 markers spaced at an average of 9-centimorgan (cM) intervals. Empirical simulations were generated to determine genome-wide significance.

RESULTS

The authors found five regions with nonparametric linkage z scores 2.0 or greater. These were the following: 2.08 was reached for D1S551 (113.7) cM at 1p31.1 and 2.31 for D2S410 (125.2 cM) at 2q14.1; 2.00 was reached for D4S2361 (93.5 cM) at 4q21.23, and 2.07 for D15S1012 (36 cM) at 15q14, the largest nonparametric linkage z score was 2.88 for D10S2327 (100.92 cM) at 10q22.3.

CONCLUSIONS

Our 10q22.3 finding at 100.9 cM is consistent with a previously reported nonparametric linkage score of 4.27 at 107.2 cM on chromosome 10, although it did not attain genome-wide significance in this study.