Asian Subpopulations Research Articles

Expanded carrier screening reveals insights into enrichment of specific disorders within a reproductive genomic space

The purpose of this study was to determine carrier frequencies in different ethnicities using a large cohort of individuals who received expanded carrier screening (ECS). Retrospective data analysis was performed on 68,517 individuals consisting of 49,617 European, 5,317 East Asian, 4,742 African and 3,503 South Asian ancestry patients referred for ECS. Documented informed consent was required for genomic analysis and data was de-identified for research purposes. ECS was performed using either an Illumina Infinium HD Custom Genotyping platform or a targeted NimbleGen Next Generation Sequencing (NGS) capture for screening of 314 recessive or X-linked disorders. Carrier frequencies were assessed in aggregate and stratified by predicted genetic ancestry (European, African, East Asian, South Asian, Native American and Native Oceanic) and self-report. General pan-ethnic discovery of at least one reportable allele was observed in 47.1% (95% CI, 46.8-47.5) of individuals. As expected, identification of reportable alleles was highest among individuals of European ancestry at 49.4% (95% CI, 48.9-49.8). For East Asian, African and South Asian ancestries one or more reportable allele was observed in 31.7% (95% CI, 30.4-32.9), 27.0% (95% CI, 25.8-28.3) and 25.1% (95%CI, 23.7-26.5) of individuals, respectively. Stratifying by ancestry revealed disorders at a high carrier frequency in non-European ancestry as compared to the extensively characterized European population. Increased carrier frequency for Alport Syndrome was observed in East Asians (1:82) as compared to Europeans (1:3800) (p=0.0295) and increased carriers for MMAB related methylmalonic acidemia were observed among African ancestry individuals (1:56) (European carrier 1:992, p=0.026). Disease frequency within East Asian subpopulations pointed to several novel insights. Self-reported Chinese (n=808), Japanese (n=198) and Korean (n=197) individuals revealed increased carriers for Wilson’s disease in those of Chinese ancestry (1:100), while Krabbe (1:50), hypophosphatasia (1:65), and McArdle Disease (1:98) were more frequently observed in those of Japanese ancestry. We summarize carrier frequency estimates in a large, pan-ethnic cohort referred for ECS. Novel insights point to variability of carrier frequencies across populations for many disorders included in this ECS panel.

Spatial mismatch beyond black and white: Levels and determinants of job access among Asian and Hispanic subpopulations

United States (US) based research suggests that distance between residency and employment constrains labour market outcomes for black Americans. Work on this phenomenon, termed spatial mismatch, suggests that residential segregation from whites shapes labour market outcomes among blacks by restricting access to job-dense suburbs. However, few studies examine patterns and drivers of spatial mismatch among Asian and Hispanic subpopulations. Using data on job counts from the 2010 Zip Code Business Patterns data set and on population counts from the 2010 US decennial Censuses, I estimate spatial mismatch for the largest ethnoracial groups in the USA: black, white, Mexican, Puerto Rican, Cuban, Indian, Chinese, Filipino, Korean, Japanese and Vietnamese Americans. To measure spatial mismatch, I create indices of dissimilarity between jobs and residency for all Metropolitan Statistical Areas (MSAs) with available data. Estimates of spatial mismatch based on panethnic categories mask subpopulation heterogeneity. Most subgroups experience higher spatial mismatch than indicated by the panethnic category. The results also show novel racial differences: the average Vietnamese and Cuban American experience higher spatial mismatch than the average black American. Segregation from whites is a central predictor of exposure to spatial mismatch across all minority groups, though findings suggest that this relationship is not driven by suburbanisation.

Clinical effect of hyperbaric oxygen therapy in the treatment of femoral head necrosis : Asystematic review and meta-analysis.

Although many clinical studies have shown that hyperbaric oxygen (HBO) therapy in the treatment of femoral head necrosis can significantly improve clinical symptoms and patients' quality of life, this conclusion has not been systematically evaluated. Therefore, ameta-analysis was performed to systematically evaluate the clinical effect of HBO therapy in the treatment of femoral head necrosis. PubMed, Embase, and Web of Science databases, as well as the reference lists of relevant studies published before August2016 were systematically searched using terms related to HBO and femoral head necrosis. Fixed or random effects models were used to estimate the pooled risk ratio (RR) with 95% confidence intervals (CI). Several subgroup analyses, sensitivity analyses, and publication bias tests were carried out to explore potential study heterogeneity and bias. Nine studies involving 305controls and 318HBO cases were included. The clinical effect in the HBO therapy group was 4.95-times higher than in the control group (odds ratio, OR= 4.95, 95%CI [3.24,7.55], P< 0.00001) and the difference was statistically significant. According to the principle of subgroup analysis, the population was divided into Asian and non-Asian subpopulations. Subgroup analyses showed that the clinical effect in the HBO therapy group was 4.77-times higher than that of the control group of the Asian subpopulation (OR= 4.77, 95%CI [3.06,7.44], P< 0.00001) and 7.07-times than that of the control group of the non-Asian subpopulation (OR= 7.07, 95%CI [1.77,28.27], P< 0.00001). The results of this study showed that HBO therapy can significantly improve the clinical treatment effect in patients with femoral head necrosis, and that this treatment approach is worthy of clinical application.

Association between MTHFR C677T polymorphism and abdominal aortic aneurysm risk: A comprehensive meta-analysis with 10,123 participants involved.

Background:Abdominal aortic aneurysm (AAA) is a life-threatening condition. A number of studies reported the association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and AAA risk, but substantial controversial findings were observed and the strength of the association remains unclear.Objective:The aim of this study was to investigate the aforementioned association in the overall population and different subgroups.Methods:PUBMED and EMBASE databases were searched until March 2016 to identify eligible studies, restricted to humans and articles published in English. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the susceptibility to AAA. Subgroup meta-analyses were conducted on features of the population, such as ethnicity, sex of the participants, and study design (source of control).Results:Twelve case–control studies on MTHFR C677T polymorphism and AAA risk, including 3555 cases and 6568 case-free controls were identified. The results revealed no significant association between the MTHFR C677T polymorphism and AAA risk in the overall population and within Caucasian or Asian subpopulations in all 5 genetic models. Further subgroup meta-analysis indicated that significantly increased risks were observed among cases with a mean age <70 years (OR = 1.73, 95% CI = 1.10–2.12, P = 0.02), cases with prevalence of smoking <60% (OR = 1.39, 95% CI = 1.02–1.90, P = 0.04), and cases with aneurysm diameter ≥55 mm (OR = 1.55, 95% CI = 1.07–2.24, P = 0.02) in the dominant genetic model. No publication bias was detected in the present study.Conclusion:In conclusion, our comprehensive meta-analysis suggests that the MTHFR C677T polymorphism may play an important role in AAA susceptibility, especially in younger, non-smoking, larger AAA-diameter subgroups of patients

Disparities in influenza vaccination across the United States: Variability by minority group, Asian sub-populations, socio-economic status, and health insurance coverage

ObjectiveThe aim of this study is to examine the effects of ethnicity, disaggregating Asian Indian from other Asians, health insurance coverage, and nativity on influenza vaccination rates in the United States. Study designNational Health Interview Survey data (2013), collected by the National Center for Health Statistics, were analysed. MethodsMultivariable regression models were used to compute estimates and 95% confidence intervals. ResultsAsian Indians had higher proportions of college graduate rates (mean = 0.85; CI = [0.80, 0.90]) and above-average income (mean = 0.56, CI = [0.48, 0.64]) than both Whites (mean = 0.406; CI = [0.39, 0.42]) and other Asian sub-groups, such as Chinese (mean = 0.544; CI = [0.47, 0.62]) and Filipino Americans (mean = 0.419; CI = [0.35, 0.48]). However, this higher socio-economic status did not uniformly translated into higher vaccine uptake rates. Asian Indian influenza vaccine uptake rate (mean = 0.403; CI = [0.33, 0.47]), while higher than Whites (mean = 0.366; CI = [0.36, 0.38]), were lower than Chinese (mean = 0.435; CI = [0.35, 0.52]) and Filipino Americans (mean = 0.431; CI = [0.37. 0.49]). In regression models, although Asian Indians were significantly more likely to receive the influenza vaccine than White Americans before controlling for health insurance status (OR = 1.38; CI = [1.004, 1.899]), when coverage was included, effects of race and ethnicity were eliminated (OR = 1.24; CI = [0.897, 1.705]). ConclusionHealth disparities research often analyses Asians as a homogenous mass; however, the availability of disaggregated data allows researchers to parse effects leading to nuanced findings which highlight behavioural diversity within groups. Findings may inform the development of targeted interventions by public health practitioners and adjustments to polices designed to improve health insurance coverage in racial and ethnic minorities, regardless of citizenship status, leading to enhanced population health.

Population-level differences in revascularization treatment and outcomes among various United States subpopulations.

Despite recent general improvements in health care, significant disparities persist in the cardiovascular care of women and racial/ethnic minorities. This is true even when income, education level, and site of care are taken into consideration. Possible explanations for these disparities include socioeconomic considerations, elements of discrimination and racism that affect socioeconomic status, and access to adequate medical care. Coronary revascularization has become the accepted and recommended treatment for myocardial infarction (MI) today and is one of the most common major medical interventions in the United States, with more than 1 million procedures each year. This review discusses recent data on disparities in co-morbidities and presentation symptoms, care and access to medical resources, and outcomes in revascularization as treatment for acute coronary syndrome, looking especially at women and minority populations in the United States. The data show that revascularization is used less in both female and minority patients. We summarize recent data on disparities in co-morbidities and presentation symptoms related to MI; access to care, medical resources, and treatments; and outcomes in women, blacks, and Hispanics. The picture is complicated among the last group by the many Hispanic/Latino subgroups in the United States. Some differences in outcomes are partially explained by presentation symptoms and co-morbidities and external conditions such as local hospital capacity. Of particular note is the striking differential in both presentation co-morbidities and mortality rates seen in women, compared to men, especially in women ≤ 55 years of age. Surveillance data on other groups in the United States such as American Indians/Alaska Natives and the many Asian subpopulations show disparities in risk factors and co-morbidities, but revascularization as treatment for MI in these populations has not been adequately studied. Significant research is required to understand the extent of disparities in treatment in these subpopulations.

Suicide rates for different religious groups in the South Asian origin population in England and Wales: a secondary analysis of a national data set

Purpose– The purpose of this paper is to calculate the rate of suicide in different religious groups in people of South Asian origin in the UK.Design/methodology/approach– A cross-sectional, secondary analysis of a national data set. A name recognition algorithm was used to identify people of South Asian origin and their religion. Standardized mortality ratios (SMRs) were calculated using this data and data from the national census. Setting: a population study of all those who died by suicide in England and Wales in 2001. Participants: all cases of suicide and undetermined intent identified by the Office for National Statistics for England and Wales.Findings– There were 4,848 suicides in the UK in 2001 of which 125 (2.6 percent) were identified as people of South Asian origin by the algorithm. The suicide rate for all people of South Asian origin was 5.50/100,000 compared to 9.31/100,000 for the population of England and Wales. The age SMR for those whose names were of Hindu, Muslim or Sikh origin were 0.88, 0.47 and 0.85, respectively. Female South Asians have lower rates of suicide, than their South Asian male counterparts.Research limitations/implications– Religious classification by the computerized program does not guarantee religious affiliation. The data set were confined to one year because religion was not collected prior to the 2001 census.Originality/value– The rates of suicide for South Asian sub-populations in the UK differ by gender and religion.

Abstract B35: Disparities in follow up after abnormal mammogram for multiple Asian subpopulations

Abstract Introduction: The burden of breast cancer among certain Asian subpopulations is higher than previously estimated, underscoring the need for close scrutiny of Asian disparities across the breast cancer continuum from prevention through survivorship. A critical point in this process, timely and complete follow-up of screening abnormalities, is known to be inadequate among women in minority groups but has not yet been studied among disaggregated Asian populations. The objective of this investigation was to assess and compare the timeliness in follow-up after abnormal mammogram among White and Asian American women in the San Francisco Bay Area. Methods: Using data from the San Francisco Mammography Registry (SFMR), we identified women with an index abnormal screening mammogram result of BIRADS 0/3+ between the years 2000-2010. Our study sample included women who self-report White or Asian race/ ethnicity, ages 30 and older who received screening services at 10 participating SFMR-facilities. We first used chi-square statistics to compare median days to diagnostic follow-up after abnormal mammogram by patient characteristics including race/ethnicity. Cumulative percent plots were constructed to visually display the percentage of racial/ethnic groups with follow-up at multiple time intervals (i.e., 30 days, 60 days). We then conducted hierarchical regression analyses that adjust for the multilevel nature of the data, controlling for within-facility clustering of observations, estimating the associations between follow-up and sociodemographic characteristics including age and education, as well as family history of breast cancer. Subgroup comparisons identified differences in these factors which might explain abnormal mammogram follow-up disparities. Results: The total sample was 54,028 women, 70% White and 30% Asian. Among Asians, 16.2% were Chinese, 6.7% Filipina, 1.8% Japanese, 1.1% Vietnamese, 2.4% Other Asian, and 1.4% Mixed Asian. The mean age of women was 53.4 years, and the majority fell within the range of 40-74 years recommended for screening. The proportion of women who did not receive follow-up within one year after an index abnormal mammogram was 11.1% (n=6023). A higher proportion of Asian women did not receive follow-up compared to Whites (15% vs 10%). Among Asian groups, Filipinas had the highest percentage of women not receiving follow-up (18%) while Japanese women had the lowest (10.4%). In comparing those who received follow-up and those who did not, a higher proportion of women with no follow-up had lower education levels (24% vs 15%). Median time to diagnostic follow-up for White and Asian women combined was 18 days. The median follow-up time was 15 days for Whites and 26 days for Asians. The median follow-up time differed significantly among Asian ethnic groups: Japanese women had the shortest (19 days) followed by Filipinas (28 days). Vietnamese women had the longest (30 days). Hierarchical regression model results with Whites and Asians, accounting for sociodemographic variables and the effect of facility, indicate that women who did not complete high school and Asian women had higher odds of no follow-up after an abnormal mammogram at 30, 60, and 90 days compared to women with a graduate degree and Whites, respectively OR 1.3, CI: 1.16-1.41, and OR 1.2, CI: 1.14-1.27. Race was no longer significant at 60 and 90 days. For regression analyses comparing Whites and Asians by ethnicity, controlling for facility, Chinese, Filipina, Other Asian and Mixed Asian were more likely than White women to not receive follow-up, even after accounting for facilities at 30 days. At 60 days, only Filipinas were significantly more likely to receive no follow-up. At 90 days, Filipina women had slightly higher odds of no follow-up compared to Whites (OR 1.1, CI: 1.02-1.28). Conclusion: We observed disparities in timeliness to follow-up between White and Asian women and among Asian ethnic groups in the first 30-days after an abnormal screening mammogram. Disaggregation of ethnicity can identify subpopulations most in need of breast cancer control, and to provide more specific information on care delivery patterns. Citation Format: Kim Hanh Nguyen, Leah Karliner, Rena Pasick. Disparities in follow up after abnormal mammogram for multiple Asian subpopulations. [abstract]. In: Proceedings of the Seventh AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 9-12, 2014; San Antonio, TX. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2015;24(10 Suppl):Abstract nr B35.

Plasma amino acid profiles in healthy East Asian subpopulations living in Japan

ObjectivesProfiles of plasma free amino acids (PFAAs) have been utilized as biomarkers to detect various diseases. However, few studies have investigated whether ethnicity or specific subpopulations within East Asia influence PFAA concentrations.MethodsA total of 95 healthy volunteers living in Japan, including 31 Japanese individuals, 36 Korean individuals and 28 Chinese individuals, were enrolled. Participants’ PFAA levels were measured by high‐performance liquid chromatography mass spectrometry, and the effects of factors such as sex, age, body mass index (BMI) and subpopulation on PFAA profiles were analyzed.ResultsWith the exception of glutamine and α‐aminobutyric acid, there were no significant differences among the three examined subpopulations with respect to either the means or the distributions of PFAA concentrations. A multiple regression analysis revealed that most of the PFAA concentrations were significantly related to sex. Ornithine concentrations, glutamate concentrations, and glutamine and α‐aminobutyric acid concentrations were significantly associated with age, BMI, and Chinese subpopulation, respectively.ConclusionThe study results indicate that the contributions of subpopulation within East Asia to PFAA profiles are small, particularly relative to the contributions provided by sex. Am. J. Hum. Biol. 28:236–239, 2016. © 2015 The Authors American Journal of Human Biology Published by Wiley Periodicals, Inc.

A pooled multisite analysis of the effects of atopic medical conditions in glioma risk in different ethnic groups

PurposeThe incidences of atopic conditions (allergies, asthma, or eczema) and glioma vary by ethnicity. Atopic conditions are inversely associated with gliomas. We conducted a pooled multisite study investigating the associations of atopic conditions with glioma in different race/ethnicity groups. MethodsUsing glioma cases and healthy controls, unconditional logistic regression was conducted to assess the associations of atopic conditions with glioma separately in white, black, Asian, and Hispanic subpopulations. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. ResultsGlioblastoma multiforme cases were less likely than controls to report a history of atopic conditions in whites (OR = 0.46, [95% CI, 0.38–0.54]) and Asians (OR = 0.27, [95% CI, 0.10–0.73]). The same trend was seen when looking at glioma cases of all histologies. An inverse association was not seen in blacks for glioblastoma multiforme or all histologies combined. ConclusionsThe inverse association between glioma and atopic conditions may vary by ethnicity due to a difference in the biology of atopic conditions in different ethnicities but may be due to chance because of the limitations of small nonwhite sample sizes.

An observational study of co-morbidities in male Caucasian and South Asian sub-populations with acute coronary syndrome

BackgroundAcute coronary syndromes (ACS) are one of the most common presentations to secondary care. In addition to established co-morbidities, ethnicity appears to play a significant role with South Asians deemed to be at particular risk. MethodsAn observational, retrospective study was performed to compare prevalence and management of co-morbidities in male South Asian versus Caucasian populations presenting with ACS. 225 patients were included. ResultsPrevalence of smoking, pre-existing hypertension and hyperlipidaemia was similar. Compliance with ACE-inhibitors/ARB, beta-blockers and high-dose statins also appeared to be comparable. South Asians demonstrated a higher prevalence of type 2 diabetes mellitus (DM) compared with Caucasians (43% versus 19%, p = 0.003), in correlation with higher average BMI (26.3 versus 22.6, p = 0.019). Requirements for ≥ 1 oral hypoglycaemic (12% versus 3%, p = 0.030) and insulin therapy (9% versus 4%, p = 0.045) was greater. South Asians also demonstrated poorer glycaemic control as defined by HbA1c > 48 mM (79% versus 58%, p = 0.004). ConclusionsResults from this study advocate a particular need to monitor glycaemic control in South Asian subgroups, who demonstrate preponderance towards type 2 DM. Cultural and language barriers may account for this disparity and require particular focus.

Efficacy and Biomarker Data From BEYOND: A Randomized Phase 3 Study of First-Line Chemotherapy ± Bevacizumab in Chinese Patients With Advanced Nonsquamous Non-Small Cell Lung Cancer: Locally Advanced Non-Small Cell Lung Cancer

Bevacizumab plus platinum-doublet chemotherapy is effective as first-line treatment for advanced nonsquamous non-small cell lung cancer (NSCLC) in global populations. The efficacy benefit seen in mainly white patients is also consistently seen in Asian subpopulations. The BEYOND study was undertaken to confirm the efficacy and safety of first-line bevacizumab plus platinum-doublet chemotherapy in Chinese NSCLC patients.

What is ‘South Asian’? A quantitative content analysis evaluating the use of South Asian ethnic categorization in Canadian health research

The use of ‘South Asian’ ethnic categorization was investigated to determine if there is consistency in its use in health research in Canada. Quantitative content analysis and a secondary qualitative content analysis were carried out on articles retrieved from a systematic review of Canadian health research conducted on ‘South Asians’ from 2005 to 2012. About 22% of articles (n = 31) examining South Asian health in Canada failed to include an explicit definition of ‘South Asian’. The failure to use a consistent operationalized definition throughout the study and the inappropriate application of findings to the relevant South Asian subpopulations were the major problems noted in the literature. Given the contextuality and fluidity of ethnic identity, the authors recommend the consistent use of explicit definitions of the specific subgroup of interest and that findings based on specific subgroups not be applied to the ‘South Asian community’ at large.

Prevalence and management of type II diabetes in caucasian and asian subpopulations with acs

Prevalence and management of type II diabetes in caucasian and asian subpopulations with acs

Prevalence of dyslipidaemia: a comparison of Caucasian and South Asian subpopulations post-ACS

Prevalence of dyslipidaemia: a comparison of Caucasian and South Asian subpopulations post-ACS

Self-Construal as a Predictor of Korean American Women's Intention to Vaccinate Daughters against Human Papillomavirus.

Korean Americans represent one of the fastest growing Asian subpopulations in the United States. Despite a dramatic reduction in incidence nationwide, cervical cancer remains a major threat for Korean American women. By preventing the strains of the Human Papillomavirus (HPV) known to cause cervical cancer, the HPV vaccines appear to be a promising solution to reduce the persistent disparities in cervical cancer among not only Korean Americans, but also other racial and ethnic minorities more generally. However, current literature lacks a better understanding of how cultural and behavioral factors influence Korean American women's intention to vaccinate their adolescent daughters against HPV. This manuscript presents the results of testing the mechanisms through which interdependent self-construal (an orientation of self in which individuals define themselves primarily through their relationships with others), attitudes, and subjective norms impact Korean American mothers' intention to vaccinate their daughters. Our findings suggest that self-construal holds promise for health communication research to not only uncover the rich variance of health-related beliefs among individuals of shared cultural descent, but also to understand the context in which these beliefs are embedded.

Insight into the Peopling of Mainland Southeast Asia from Thai Population Genetic Structure

There is considerable ethno-linguistic and genetic variation among human populations in Asia, although tracing the origins of this diversity is complicated by migration events. Thailand is at the center of Mainland Southeast Asia (MSEA), a region within Asia that has not been extensively studied. Genetic substructure may exist in the Thai population, since waves of migration from southern China throughout its recent history may have contributed to substantial gene flow. Autosomal SNP data were collated for 438,503 markers from 992 Thai individuals. Using the available self-reported regional origin, four Thai subpopulations genetically distinct from each other and from other Asian populations were resolved by Neighbor-Joining analysis using a 41,569 marker subset. Using an independent Principal Components-based unsupervised clustering approach, four major MSEA subpopulations were resolved in which regional bias was apparent. A major ancestry component was common to these MSEA subpopulations and distinguishes them from other Asian subpopulations. On the other hand, these MSEA subpopulations were admixed with other ancestries, in particular one shared with Chinese. Subpopulation clustering using only Thai individuals and the complete marker set resolved four subpopulations, which are distributed differently across Thailand. A Sino-Thai subpopulation was concentrated in the Central region of Thailand, although this constituted a minority in an otherwise diverse region. Among the most highly differentiated markers which distinguish the Thai subpopulations, several map to regions known to affect phenotypic traits such as skin pigmentation and susceptibility to common diseases. The subpopulation patterns elucidated have important implications for evolutionary and medical genetics. The subpopulation structure within Thailand may reflect the contributions of different migrants throughout the history of MSEA. The information will also be important for genetic association studies to account for population-structure confounding effects.

Nucleotide diversity of vernalization and flowering‐time‐related genes in a germplasm collection of meadow fescue (Festuca pratensis Huds. syn. Lolium pratense (Huds.) Darbysh.)

In plant species, control of flowering time is an important factor for adaptation to local natural environments. The Vrn1, CO, FT1 and CK2α genes are key components in the flowering-specific signaling pathway of grass species. Meadow fescue is an agronomically important forage grass species, which is naturally distributed across Europe and Western Asia. In this study, meadow fescue flowering-time-related genes were resequenced to assess nucleotide diversity in European and Western Asian subpopulations. Identified sequence polymorphisms were then converted into PCR-based molecular genetic markers, and a meadow fescue germplasm collection was genotyped to investigate global allelic variation. Lower nucleotide diversities were observed for the Vrn1 and CO orthologs, while relatively higher values were observed for the FT1 and casein kinase II α-subunit (CK2α) orthologs. The nucleotide diversity for FT1 orthologs in the Western Asian subpopulation was significantly higher than those of the European subpopulation. Similarly, significant differences in nucleotide diversity for the remaining genes were observed between several combinations of subpopulation. The global allele distribution pattern was consistent with observed level of nucleotide diversity. These results suggested that the degree of purifying selection acting on the genes differs according to geographical location. As previously shown for model plant species, functional specificities of flowering-time-related genes may also vary according to environmental conditions.

Trends and projections of annual birth volumes in the State of Qatar: 1970–2025

Background: The ethnic profile of Qatar is a combination of its indigenous peoples (Qataris) and non-resident foreigners (non-Qataris). Its population has increased dramatically during the last 30 years to around 1.9 m (although only 15% are Qataris) leading to an increase in the number of local births. A recent unexpected surge in births has lead to a need to re-evaluate the trends in birth numbers and develop more reliable predictions for both near- (2015) and far-term (2025) annual numbers of births to support the many healthcare planning initiatives which are currently underway. Methods: There is considerable information already available in Qatar which can facilitate such a study. This paper collates these various data, charts and investigates their visible trends and develops a simple mathematical model which projects the annual number of births which might reasonably be expected to emerge later in this decade and beyond. Results: The Qatari sub-population has maintained a reliable linear increase in birth numbers since data first began to be collected. The births among the non-GCC and Asian sub-populations are the primary cause of the recent nonlinear increase which can be well-described in the near-term by a simple quadratic curve. Far-term projections require a non-linear mathematical model which combines the regular linear increase among the Qataris with an exponentially decreasing demand for “in-Qatar” births from the non-Qataris. The trend for multiple births in Qatar (i.e. the annual number of live-born twins, triplets etc.) has shown significant increases during the last 20 years but may be reaching a plateau. Among Qataris the numbers have been higher but – at least for triplets and higher-order births – this gap has decreased in the last few years. It appears that the increase in multiple births has been associated with the current expansion of IVF programs and other forms of assisted conception in Qatar. Conclusions: The annual number of births in Qatar has recently shown a significant departure from its previous trend, requiring a radical reassessment of future projections. There has also been a concomitant increase in multiple births which has been associated with the expansion of IVF programs and other forms of assisted conception. A simple quadratic model predicts that there will be ∼22,500 births in 2015, of which ∼8,000 will be Qatari. A far-term projection for 2025 suggests that this number is likely to rise to ∼27,000 but with some small additional increase yet to come.

Ethnic differences in the relationship between insulin sensitivity and insulin response: a systematic review and meta-analysis.

OBJECTIVEHuman blood glucose levels have likely evolved toward their current point of stability over hundreds of thousands of years. The robust population stability of this trait is called canalization. It has been represented by a hyperbolic function of two variables: insulin sensitivity and insulin response. Environmental changes due to global migration may have pushed some human subpopulations to different points of stability. We hypothesized that there may be ethnic differences in the optimal states in the relationship between insulin sensitivity and insulin response.RESEARCH DESIGN AND METHODSWe identified studies that measured the insulin sensitivity index (SI) and acute insulin response to glucose (AIRg) in three major ethnic groups: Africans, Caucasians, and East Asians. We identified 74 study cohorts comprising 3,813 individuals (19 African cohorts, 31 Caucasian, and 24 East Asian). We calculated the hyperbolic relationship using the mean values of SI and AIRg in the healthy cohorts with normal glucose tolerance.RESULTSWe found that Caucasian subpopulations were located around the middle point of the hyperbola, while African and East Asian subpopulations are located around unstable extreme points, where a small change in one variable is associated with a large nonlinear change in the other variable.CONCLUSIONSOur findings suggest that the genetic background of Africans and East Asians makes them more and differentially susceptible to diabetes than Caucasians. This ethnic stratification could be implicated in the different natural courses of diabetes onset.