Heritability of adult body height: a comparative study of twin cohorts in eight countries.

A major component of variation in body height is due to genetic differences, but environmental factors have a substantial contributory effect. In this study we aimed to analyse whether the genetic architecture of body height varies between affluent western societies. We analysed twin data from eight countries comprising 30,111 complete twin pairs by using the univariate genetic model of the Mx statistical package. Body height and zygosity were self-reported in seven populations and measured directly in one population. We found that there was substantial variation in mean body height between countries; body height was least in Italy (177 cm in men and 163 cm in women) and greatest in the Netherlands (184 cm and 171 cm, respectively). In men there was no corresponding variation in heritability of body height, heritability estimates ranging from 0.87 to 0.93 in populations under an additive genes/unique environment (AE) model. Among women the heritability estimates were generally lower than among men with greater variation between countries, ranging from 0.68 to 0.84 when an additive genes/shared environment/unique environment (ACE) model was used. In four populations where an AE model fit equally well or better, heritability ranged from 0.89 to 0.93. This difference between the sexes was mainly due to the effect of the shared environmental component of variance, which appears to be more important among women than among men in our study populations. Our results indicate that, in general, there are only minor differences in the genetic architecture of height between affluent Caucasian populations, especially among men.     

Incidence and thickness of primary tumours and survival of patients with cutaneous malignant melanoma in relation to socioeconomic status.

OBJECTIVE--To study incidence of and survival from cutaneous malignant melanoma in relation to socioeconomic status. DESIGN--Application of Carstairs deprivation score to all malignant melanoma patients diagnosed in a geographically defined area over a 15 year period. SETTING--West of Scotland (area population 2,716,900). SUBJECTS--3142 patients first diagnosed with malignant melanoma in the period 1979-93. INTERVENTIONS--Surgical excision of primary malignant melanoma with additional treatment as appropriate and follow up until December 1994. MAIN OUTCOME MEASURES--Malignant melanoma incidence, primary tumour thickness and five year survival by socioeconomic status. RESULTS--From 1979 to 1993, the age standardised incidence rate for cutaneous malignant melanoma was 9.1/100,000 for the most affluent men and 2.4/100,000 for the least affluent men and 16.1/100,000 and 5.0/100,000 respectively for most and least affluent women (P < 0.001 for trend in both). The incidence increased steadily over time in both sexes in all socioeconomic groups. Good prognosis tumours ( < 1.5 mm thick) were most common in the most affluent men and women, and over the study period the proportion of such tumours increased most in the intermediate affluence group (both sexes) and in the least affluent women. Five year disease free survival from melanoma for the sexes combined was 81% for most affluent, 77% for intermediate, and 73% for least affluent groups. Even after adjustment for known prognostic factors of tumour thickness, ulceration, age, and body site of primary melanoma, the more affluent the group, the better the survival. CONCLUSION--Although the incidence of cutaneous malignant melanoma is higher among more affluent people, the prognosis is better in this group than for less affluent individuals. Early diagnosis campaigns should be targeted particularly to less affluent men and primary prevention campaigns should emphasise the greater risk in more affluent women.     

Re-imagining the Diaspora: History, Responsibility, and Commitment in an Age of Globalization

The past two decades have witnessed the intensification of globalization and the unprecedented exodus of Africans to developed countries. The two trends have profound implications for the North and South and also for Africans and their relationship to their homeland. This paper examines the relationship and explores the challenges of engaging, interrogating and re-imaging the notion of Diaspora. This paper is dedicated to the memory of Professor Michael C. Mbabuike, “Ugonabo” – an accomplished poet, a distinguished scholar, a most valued colleague, a brother in the truest sense of the word, a decent man – with whom I shared an immense love for our homeland, Igboland.     

Estimation of secular trends in adult height, and childhood socioeconomic circumstances in three Eastern European populations

The objective of these analyses was to estimate the strength and direction of secular trends in adult height and childhood socioeconomic circumstances in eight towns in three Eastern European countries in the mid-20th century, and to assess the extent to which childhood conditions might explain the height differences. We used cross-sectional data from the baseline survey of the Health, Alcohol and Psychosocial factors in Eastern Europe (HAPIEE) study, conducted in 2002-2005. The study examined 24,012 men and women born between 1933 and 1957, randomly selected from the general populations of Novosibirsk (Russia), Krakow (Poland) and six towns of the Czech Republic. To allow for age-related height loss we estimated maximum attained height. Parental education and household item ownership at age 10 were used as markers of childhood socioeconomic conditions. In all 5-year birth cohorts, Novosibirsk men and women were shortest. There were positive and statistically significant secular trends in childhood conditions and in maximum adult height. Adjustment for childhood conditions explained about one third of the trend in height. There appeared to be a small reduction in height of persons born during the Second World War which was, however, only significant in Novosibirsk. These results suggest that secular trends in height mirror, but are not wholly explained by, trends in socioeconomic circumstances in early life.     

Palm and sole interdigital ridge-count correlations

Correlations among the twelve palm and sole interdigital ridge-counts were calculated for samples of Europeans of German, Austrian, Finnish and Polish ancestry, for Bantu speaking Black Africans from Angola and the Republic of South Africa, for Japanese and Tibetans and for Indians and Coloureds from the Republic of South Africa. Canonical correlation and factor analyses were used to discern patterning in the correlations. Generally, within palm and within sole correlations are stronger than palm-sole correlations. However, the results show an unequivocal positive relationship between palm and sole ridge-counts. A consistent feature was a stronger relationship of palm c-d counts to sole a-b counts. We suggest that this pattern of correlation may reflect early morphogenetic pattern formation prior to commitment of cells to hands and feet.     

Relation between socioeconomic deprivation and pathological prognostic factors in women with breast cancer.

OBJECTIVE--To investigate the relation between socioeconomic deprivation and pathological prognostic factors in women with breast cancer as a possible explanation for socioeconomic differences in survival. DESIGN--Retrospective analysis of data from cancer registry and from pathology and biochemistry records. SETTING--Catchment areas of two large teaching hospitals in Glasgow. SUBJECTS--1361 women aged under 75 who had breast cancer diagnosed between 1980 and 1987. MAIN OUTCOME MEASURES--Tumour size, axillary lymph node status, histological grade, and oestrogen receptor concentration in relation to deprivation category of area of residence. RESULTS--There was no significant relation between socioeconomic deprivation and four pathological prognostic factors: 93 (32%) women in the most affluent group presented with tumours less than 20 mm in size compared with 91 (31%) women in the most deprived group; 152 (48%) of the most affluent group presented with negative nodes compared with 129 (46%) of the most deprived group; 23 (22%) of the most affluent group presented with grade I tumours compared with 12 (17%) of the most deprived group; and 142 (51%) of the most affluent group had a low oestrogen receptor concentration at presentation compared with 148 (52%) of the most deprived group. None of these differences was statistically significant. CONCLUSIONS--Differences in survival from breast cancer by socioeconomic deprivation category could not be accounted for by differences in tumour stage or biology. Other possible explanations, such as differences in treatment or in host response, should be investigated.     

Waist Circumference,BMI, and Visceral Adipose Tissue in White Women and Women of African Descent

Although waist circumference (WC) is a marker of visceral adipose tissue (VAT), WC cut‐points are based on BMI category. We compared WC‐BMI and WC‐VAT relationships in blacks and whites. Combining data from five studies, BMI and WC were measured in 1,409 premenopausal women (148 white South Africans, 607 African‐Americans, 186 black South Africans, 445 West Africans, 23 black Africans living in United States). In three of five studies, participants had VAT measured by computerized tomography (n = 456). Compared to whites, blacks had higher BMI (29.6 ± 7.6 (mean ± s.d.) vs. 27.6 ± 6.6 kg/m², P = 0.001), similar WC (92 ± 16 vs. 90 ± 15 cm, P = 0.27) and lower VAT (64 ± 42 vs. 101 ± 59 cm², P < 0.001). The WC‐BMI relationship did not differ by race (blacks: β (s.e.) WC = 0.42 (.01), whites: β (s.e.) WC = 0.40 (0.01), P = 0.73). The WC‐VAT relationship was different in blacks and whites (blacks: β (s.e.) WC = 1.38 (0.11), whites: β (s.e.) WC = 3.18 (0.21), P < 0.001). Whites had a greater increase in VAT per unit increase in WC. WC‐BMI and WC‐VAT relationships did not differ among black populations. As WC‐BMI relationship did not differ by race, the same BMI‐based WC guidelines may be appropriate for black and white women. However, if WC is defined by VAT, race‐specific WC thresholds are required.     

‘Our fellow Africans make our lives hell’: the lives of Congolese and Nigerians living in Johannesburg

Xenophobia in post-apartheid South Africa has become a major issue. Much of the hostility is directed at Africans from countries north of Southern Africa who are often easily distinguishable due to their physical features, distinctive dress and inability to speak the indigenous languages. This article focuses on immigrants and asylum seekers from two countries, Nigeria and the Democratic Republic of Congo. Both groupings have experienced significant antagonism and prejudice from the local population, more especially from black South Africans. The article describes and analyses the interaction of the two groupings in question with the local populace and authorities. What is argued is that during the apartheid era the restrictions on black immigration meant that the number of black foreigners was limited. Since 1990, however, there has been a substantial increase in illegal and legal migration from Southern African countries and countries further north. This increase, in a context of growing unemployment and crime, limited infrastructural growth and fiscal resources, has intensified xenophobia against foreign Africans. The article is mainly based on in-depth interviews with Nigerian and Congolese informants living in Johannesburg's inner city.     

A socioeconomic analysis of secular trends in isonymy in the Jewish community of Gibraltar: 1820 to 1939

This study examines secular trends in the magnitude of inbreeding in the Jewish community of Gibraltar over a 120 year period. Analysis of isonymous unions by socioeconomic status revealed distinctive differences between high versus mid/low status unions. Factors responsible for the elevated rate of inbreeding among the professional/mercantile class and its secular trend are discussed.     

Why Are There Social Gradients in Preventative Health Behavior? A Perspective from Behavioral Ecology

Background

Within affluent populations, there are marked socioeconomic gradients in health behavior, with people of lower socioeconomic position smoking more, exercising less, having poorer diets, complying less well with therapy, using medical services less, ignoring health and safety advice more, and being less health-conscious overall, than their more affluent peers. Whilst the proximate mechanisms underlying these behavioral differences have been investigated, the ultimate causes have not.

Methodology/Principal Findings

This paper presents a theoretical model of why socioeconomic gradients in health behavior might be found. I conjecture that lower socioeconomic position is associated with greater exposure to extrinsic mortality risks (that is, risks that cannot be mitigated through behavior), and that health behavior competes for people''s time and energy against other activities which contribute to their fitness. Under these two assumptions, the model shows that the optimal amount of health behavior to perform is indeed less for people of lower socioeconomic position.

Conclusions/Significance

The model predicts an exacerbatory dynamic of poverty, whereby the greater exposure of poor people to unavoidable harms engenders a disinvestment in health behavior, resulting in a final inequality in health outcomes which is greater than the initial inequality in material conditions. I discuss the assumptions of the model, and its implications for strategies for the reduction of health inequalities.     

On sociogenetic clines

Both in England and Chile the A blood group is found more frequently in the higher socioeconomic strata. The O group behaves inversely. This seems to be true, at least, for blood donors in England and for the general population in Chile. This sociogenetic cline interacts with sex, being less evident in women. In Chile the Rh system shows a cline with a higher frequency of the Rh(-) or d allele in higher socioeconomic strata. The Chilean population originated from the admixture of Europeans (mostly Spaniards) and Chilean aborigines (since 1541). Spaniards had high frequencies of the A and d alleles and an appreciable frequency of the B alleles. Chilean aborigines had very low frequencies or totally lacked these alleles. Spaniards maintained the higher socioeconomic strata and manual labor was performed by mestizos or aborigines. Thus the Chilean sociogenetic cline was explained by ethnic admixture, socioeconomic discrimination, and socioeconomic assortative mating. The present results show that the exclusive historical and cultural explanation of the cline is not sufficient and a genetic factor should be added to the former ones. The distribution of the ABO groups in England and Chile were found to be similar only in stratum I, the other strata being strikingly different. The AB and B groups did not reflect the cline in either population. The Chilean stratum I showed higher d and lower O gene frequencies than present Spaniards populations, a result that cannot be explained by cultural factors. The distribution of ABO groups in a sample of Chilean medical students and in children from public schools showed a strong interaction with sex. No genetic mechanism can be proposed to fit these results, however psychological heterosis seems a good approximation.     

Toxoplasmosis snapshots: Global status of Toxoplasma gondii seroprevalence and implications for pregnancy and congenital toxoplasmosis

Toxoplasma gondii’s importance for humans refers mainly to primary infection during pregnancy, resulting in abortion/stillbirth or congenital toxoplasmosis. The authors sought to evaluate the current global status of T. gondii seroprevalence and its correlations with risk factors, environmental and socioeconomic parameters. Literature published during the last decade on toxoplasmosis seroprevalence, in women who were pregnant or of childbearing age, was retrieved. A total of 99 studies were eligible; a further 36 studies offered seroprevalence data from regions/countries for which no data on pregnancy/childbearing age were available. Foci of high prevalence exist in Latin America, parts of Eastern/Central Europe, the Middle East, parts of south-east Asia and Africa. Regional seroprevalence variations relate to individual subpopulations’ religious and socioeconomic practices. A trend towards lower seroprevalence is observed in many European countries and the United States of America (USA). There is no obvious climate-related gradient, excluding North and Latin America. Immigration has affected local prevalence in certain countries. We further sought to recognise specific risk factors related to seropositivity; however, such risk factors are not reported systematically. Population awareness may affect recognition of said risks. Global toxoplasmosis seroprevalence is continuingly evolving, subject to regional socioeconomic parameters and population habits. Awareness of these seroprevalence trends, particularly in the case of women of childbearing age, may allow proper public health policies to be enforced, targeting in particular seronegative women of childbearing age in high seroprevalence areas.     

Decreasing Fires in Mediterranean Europe

Forest fires are a serious environmental hazard in southern Europe. Quantitative assessment of recent trends in fire statistics is important for assessing the possible shifts induced by climate and other environmental/socioeconomic changes in this area. Here we analyse recent fire trends in Portugal, Spain, southern France, Italy and Greece, building on a homogenized fire database integrating official fire statistics provided by several national/EU agencies. During the period 1985-2011, the total annual burned area (BA) displayed a general decreasing trend, with the exception of Portugal, where a heterogeneous signal was found. Considering all countries globally, we found that BA decreased by about 3020 km² over the 27-year-long study period (i.e. about -66% of the mean historical value). These results are consistent with those obtained on longer time scales when data were available, also yielding predominantly negative trends in Spain and France (1974-2011) and a mixed trend in Portugal (1980-2011). Similar overall results were found for the annual number of fires (NF), which globally decreased by about 12600 in the study period (about -59%), except for Spain where, excluding the provinces along the Mediterranean coast, an upward trend was found for the longer period. We argue that the negative trends can be explained, at least in part, by an increased effort in fire management and prevention after the big fires of the 1980’s, while positive trends may be related to recent socioeconomic transformations leading to more hazardous landscape configurations, as well as to the observed warming of recent decades. We stress the importance of fire data homogenization prior to analysis, in order to alleviate spurious effects associated with non-stationarities in the data due to temporal variations in fire detection efforts.     

Medical Students in Canadian Universities: Report of Statistics, 1965-66

Enrolment in the 12 Canadian medical schools in 1965-66 reached a new high of 4023, an increase of 3.8% over 1964-65. The percentage of women among medical students (11.4%) was close to that for the preceding two years. The decline in the numbers of students from outside Canada continued into the present year; in 1965-66, 9.1% of medical students were non-Canadian. This decline has been primarily in the number of students from the U.S.A. The number of students from Commonwealth countries has shown a steady increase over the seven-year period under review; in 1965-66 they make up nearly one-half of all non-Canadian students. It was noted that 27% of overseas students came to Canada under governmental or intergovernmental sponsorship. Of the Canadian students, 95% came from the “home” provinces of the medical schools.     

Peak Waste: When Is It Likely to Occur?

Population and per capita gross domestic product (GDP) projections are used to estimate total global municipal solid waste (MSW) generation over the twenty‐first century. Some projections for global population suggest that it will peak this century. Waste generation rates per capita generally increase with affluence, although in the most affluent countries there is also a trend toward dematerialization. The confluence of these factors means that at some point in the future total global waste generation could possibly peak. To determine when peak waste might occur, we used the shared‐socioeconomic pathway scenarios (used in Intergovernmental Panel on Climate Change [IPCC] studies) combined with estimates of municipal solid waste (MSW) generation rates, extrapolated from our work for the World Bank. Despite the expectation that total MSW generation in Organisation for Economic Co‐operation and Development (OECD) and high‐income countries will peak mid‐century, with current trajectories global peak waste is not expected before 2100. The peak could be moved forward to around 2075 and reduced in intensity by some 30% if a more aggressive sustainability growth scenario were followed, rather than the current business‐as‐usual scenario. Further, the magnitude of peak waste is sensitive to the intensity of waste generation; it could vary from 7.3 to 10.9 megatonnes per day under the sustainability scenario. The timing of peak waste will substantially depend on the development of cities in Sub‐Saharan Africa, where population growth rates are more than double the rest of the world.     

Medical Students in Canadian Universities: Report of Statistics, 1966-67

Enrolment in the 13 Canadian medical schools in 1966-67 reached a new high of 4230, an increase of 5.1% over 1965-66. The percentage of women among medical students (12.1%) was close to that of the preceding three years. There has been a levelling off in the decline of students from outside Canada in 1966-67, when 9.5% of medical students were non-Canadian. The decline had been primarily in the number of American students, which continues. The number of students from Commonwealth countries has shown a steady increase during the eight-year period under review; in 1966-67, they make up nearly one-half of all non-Canadian students. It was noted that 18.5% of overseas students came to Canada under governmental or intergovernmental sponsorship. Of the Canadian students, 94% came from the “home” provinces of the medical schools.     

Patrilineal family values,family planning and variation in stature among Taiwanese six-year-olds

It has been argued that patrilineal joint family systems tend to bias family planning decisions in favour of sons. A simple model suggests that in such societies, any given son will be more highly valued by his parents (1) the fewer his brothers and (2) the earlier his birth is in the brother series. A daughter's value will be greater (1) the fewer brothers she has and (2) the earlier her birth is relative to other sisters. This study first addresses the extent of son preference as inferred from family composition data for 772 Taiwanese first-graders born in the mid-1970s in two socioeconomically distinct communities in Taipei, Taiwan. It then uses linear regression to consider whether the model criteria help account for statural variation among children in each study area when controlling for differences in measurement age, parental education and housing. With respect to family composition and gender preference, available evidence was consistent with previous surveys. While better-educated parents in the more affluent study area had significantly fewer children (p < 0.0005) and were more willing to stop without a son, girls there, as in the less affluent area, were still significantly more likely than boys to belong to large sibships (p < or = 0.005). Evidence from mean height of males and females partially accords with hypothetical predictions. In the less affluent area, the interaction effect of male birth order and the presence of younger siblings was significantly associated with mean stature (p = 0.002). Males without brothers were 2.0 cm taller than males with either an older or a younger brother (116.3 +/- 0.5 cm vs 114.3 +/- 0.4 cm). Males who had both younger and older brothers, but often no sisters, were about as tall, however, as those without brothers. A similar, but less pronounced, pattern was found among males in the more affluent area, but only among those who had sisters. These boys were also consistently shorter than boys without sisters (115.6 +/- 0.6 cm vs 117.7 +/- 0.6 cm; p = 0.001). Patterns of mean female stature did not clearly support the hypothesis. Girls in the more affluent area were relatively tall and did not show significant variation. Results among less affluent girls showed significant contrasts, but not necessarily in the predicted direction.     

Influence of socioeconomic status on design of Batswana home gardens and associated plant diversity patterns in northern South Africa

Over the last two decades, home garden studies have markedly increased in both developed and developing countries. However, garden design and its influence on the overall biodiversity of the urban green infrastructure remains a neglected aspect of home garden research. Home garden surveys were conducted in the North West and Gauteng Provinces of South Africa to contribute to this research focus. The two questions asked in this paper were: (1) Are Batswana garden designs associated with socioeconomic status (SES)? (2) Are the different garden designs characterized by specific plant species richness patterns? We hypothesized that SES influences garden design and that, as the SES of Batswana residents increases, the garden design changes from tshimo to colonial. Our results indicated that garden design reflected less cultural influences and took on a more Westernized colonial design appearance with improvement of SES of Batswana inhabitants. Tshimo gardens tended to have more native and utilitarian species. In contrast, colonial gardens have more alien ornamental species. In affluent areas, sampled Batswana gardens completely changed from a tshimo to colonial garden design. This change indicates that improved socioeconomic status overrides traditional cultural practices.