Genetic structure of the tiger mosquito, Aedes albopictus, in Cameroon (Central Africa)

Background

Aedes albopictus (Skuse, 1884) (Diptera: Culicidae), a mosquito native to Asia, has recently invaded all five continents. In Central Africa it was first reported in the early 2000s, and has since been implicated in the emergence of arboviruses such as dengue and chikungunya in this region. Recent genetic studies of invasive species have shown that multiple introductions are a key factor for successful expansion in new areas. As a result, phenotypic characters such as vector competence and insecticide susceptibility may vary within invasive pest species, potentially affecting vector efficiency and pest management. Here we assessed the genetic variability and population genetics of Ae. albopictus isolates in Cameroon (Central Africa), thereby deducing their likely geographic origin.

Methods and Results

Mosquitoes were sampled in 2007 in 12 localities in southern Cameroon and analyzed for polymorphism at six microsatellite loci and in two mitochondrial DNA regions (ND5 and COI). All the microsatellite markers were successfully amplified and were polymorphic, showing moderate genetic structureamong geographic populations (F_ST = 0.068, P<0.0001). Analysis of mtDNA sequences revealed four haplotypes each for the COI and ND5 genes, with a dominant haplotype shared by all Cameroonian samples. The weak genetic variation estimated from the mtDNA genes is consistent with the recent arrival of Ae. albopictus in Cameroon. Phylogeographic analysis based on COI polymorphism indicated that Ae. albopictus populations from Cameroon are related to tropical rather than temperate or subtropical outgroups.

Conclusion

The moderate genetic diversity observed among Cameroonian Ae. albopictus isolates is in keeping with recent introduction and spread in this country. The genetic structure of natural populations points to multiple introductions from tropical regions.     

Challenges Faced by Behavioral Genetic Studies: Researchers Perspective from the MENA Region

BackgroundBehavioral genetic studies are important for the understanding of the contribution of genetic variations to human behavior. However, such studies might be associated with some ethical concerns.MethodsIn the current study, ethical challenges related to studies of genetic variations contributing to human behavior were examined among researchers. To achieve the study purpose, the Middle East and North Africa (MENA) region researchers were taken as an example, where the after- mentioned ethical challenges were discussed among a group of researchers, who were the participants of an online forum. Discussions and responses of the participants were monitored and were later qualitatively analyzed.ResultsDiscussions revealed that several ethical challenges, including subjects’ recruitment, the difficulty of obtaining informed consents, and issues of privacy and confidentiality of obtained data as information leakage, in this case, will lead to social stigma and isolation of the participants and their immediate family members. Jordanian social and cultural norms, faith, and the tribal nature of the population were raised as a major challenge that might face conducting behavioral genetic studies in the Arab populations of the MENA. The lack of regulation related to the conduction of genetic studies, misunderstanding, and misuse of genetic information are other challenges. A full explanation of genetic research and the current and future possible benefits/risks of such research could be potential solutions.ConclusionIn conclusion, the MENA populations are tackled with major challenges in relation to conducting research studies in genetics/antisocial behavior field/s. Establishment of guidelines related to genetic studies, capacity building, increasing public awareness about the importance of genetic testing, and enhancing responsible conduct of research will facilitate the conduct of such sensitive studies in the future in the region.     

"They want to know where they came from": population genetics, identity, and family genealogy

This paper discusses the changing relationship between population genetics, family genealogy and identity. It reports on empirical research with participants in a genetic study who anticipated that personal feedback on the analysis of their donated samples would elucidate aspects of their own family genealogies. The paper also documents how geneticists, building on the practices of offering personal feedback to research participants, have developed genetic tests marketed directly to people wishing to trace their ancestry. Some of the social and ethical issues raised by this development in the use of genetic testing are considered.     

“They want to know where they came from”: population genetics,identity, and family genealogy

This paper discusses the changing relationship between population genetics, family genealogy and identity. It reports on empirical research with participants in a genetic study who anticipated that personal feedback on the analysis of their donated samples would elucidate aspects of their own family genealogies. The paper also documents how geneticists, building on the practices of offering personal feedback to research participants, have developed genetic tests marketed directly to people wishing to trace their ancestry. Some of the social and ethical issues raised by this development in the use of genetic testing are considered.     

Linkage of genetics and ethics: more crossing over is needed

Since the development of recombinant DNA technology in the mid 1970s, there has been increasing interest in the ethical, legal, and social implications of genetics and related fields. The web sites of five different organizations (government, academic, and independent not-for-profit) that deal explicitly with genetics and ethics are reviewed here. Some of the sites cover genetics and other issues in bioethics while others cover human genetics exclusively. The target audiences for the sites include medical and scientific professionals, students, and the general public. Among the issues examined are genetic testing, genetic discrimination in employment and health insurance, genetically modified foods, stem cells and DNA patenting. Resources for those interested in legal issues are particularly well-represented on these sites.     

The Disclosure of Genetic Information: A Human Research Ethics Perspective

Increasing emphasis on genetic research means that growing numbers of human research projects in Australia will involve complex issues related to genetic privacy, familial information and genetic epidemiology. The Office of Population Health Genomics (Department of Health, Western Australia) hosted an interactive workshop to explore the ethical issues involved in the disclosure of genetic information, where researchers and members of human research ethics committees (HRECs) were asked to consider several case studies from an ethical perspective. Workshop participants used a variety of approaches to examine the complex ethical issues encountered, but did not consistently refer to the values and principles outlined in the National Statement on Ethical Conduct in Human Research (NHMRC 2007) or apply rational ethical approaches. Overall, the data suggested that both researchers and HREC members may benefit from further education and support regarding the application of ethical frameworks to the issues encountered in genetic research.     

生物样本库及其伦理问题简介

随着分子和基因组信息对流行病学影响的增加,无数遗传流行病学研究和后人类基因组计划的研究都越来越依赖人类生物样本库的使用。生物样本库的范围也已横跨学术或者医院环境下的小数量收集到大规模的全国性储藏。尽管生物样本库的概念并不新,但是在基因组研究和后人类基因组计划的背景下,伴随它们十几年极大发展的是无数待解决的伦理挑战。从生物样本库的概念着手,介绍了其与一般遗传数据库的区别以及建立生物样本库的意义;然后介绍并比较国际上已有的生物样本库,以及其伦理问题和伦理法律框架的发展趋势。     

Bioethics for human geneticists: models for reasoning and methods for teaching.

The ethical issues raised by the Human Genome Project (HGP) and by human genetics in general are not entirely novel. In fact, the ethical issues surrounding genetic research and the provision of genetic services fit into the evolution of bioethics, a field of inquiry which has its roots in concerns of the 1970s, concerns about the dignity and self-determination of individuals and about the development of medical technologies. Although bioethics has been largely occupied with patient-centered concerns, attention is currently shifting toward socially oriented issues, such as the justice of the existing health-care system. Genetic counseling has already incorporated many of the lessons of early bioethics and, as a profession, adheres to a consultand-centered ethic which reflects the values incorporated into the doctrine of informed consent, which is a cornerstone of bioethics. The mandate of the Ethical, Legal, and Social Implications Program of the HGP--to anticipate ethical problems arising from advances in genetics and to educate the public about genetics--reflects not only the nonpaternalistic approach of early bioethics but also bioethics' increasing attention to the ethical import of systemic and institutional factors, as well as an anticipatory and preventive approach to dealing with ethical concerns. Because bioethics has so much to contribute to current consideration of ethical issues in human genetics, it is important to provide training in ethics to those working in the field. Guidelines for using a case-oriented approach are suggested.     

Ethical issues and GenomEUtwin.

The post-genomic era is witnessing a proliferation of large-scale and population based genetic and genomic research projects. Many countries have or are establishing research biobanks and, as with GenomEUtwin, there is great interest in building multinational projects that link genotypic and phenotypic information from different centers. Clearly, the conduct of these projects raises multiple ethical issues, and the knowledge generated will continually recast the ethical, legal and social implications (ELSI) of such research. Maximising the scientific profit from this work while minimizing the risks to the participants requires full integration of ethics components into the structure and functioning of these projects. GenomEUtwin is organized around five intellectual cores, including an Ethics Core which operates across the entire project. This paper describes the role of the Ethics Core and presents an overview of the guidelines on which the principles followed in GenomEUtwin are based. We outline the major ethical concerns of our project and highlight complexities arising from diverse national legislations. Finally, the role of empirically based ethics research is discussed for understanding the ethical, legal, social and economic implications of human genetics and genomics research.     

Human genome research and the public interest: progress notes from an American science policy experiment.

This essay reviews the efforts of the U.S. Human Genome Project to anticipate and address the ethical, legal, and social implications of new advances in human genetics. Since 1990, approximately $10 million has been awarded by the National Institutes of Health and the Department of Energy, in support of 65 research, education, and public discussion projects. These projects address four major areas of need: (1) the need for both client-centered assessments of new genetic services and for improved knowledge of the psychosocial and ethnocultural factors that shape clients' clinical genetic experiences; (2) the need for clear professional policies regarding human-subject research, clinical practice standards, and public health goals in human genetics; (3) the need for social policy protection against unfair access to and use of personal genetic information; and (4) the need for improved public and professional understanding and discussion of these issues. The Human Genome Project's goal is to have defined, by 1995, policy options and programs capable of addressing these needs.     

On applications of landscape genetics

Recent assertions in the literature (e.g., Keller et al. 2015) suggest that landscape genetic research has been infrequently applied by practitioners. We were interested to test this assertion, which is difficult to assess, since applications may not be detectable through searches of peer-reviewed literature. Producing publications may not be a goal of practitioners. We developed a method to search the internet for evidence of research applications and evaluated 25 different research fields in the natural sciences. We found that fields with more publications also had more applications, but the field of landscape genetics was less applied than expected based on the number of peer-reviewed publications—only about 4 % of landscape genetics articles were applied. In fact, all research fields in genetics or evolutionary biology were under-applied compared to ‘whole organism’, ecological research fields. This result suggests the lack of applications in landscape genetics may be due to a systemic under-application of genetics research, perhaps related to a lack of understanding of genetics by practitioners. We did find some evidence of landscape genetic applications however, which we sorted into 5 categories: (1) identification of evolutionarily significant units for conservation, (2) managing pathogens and invasive species, (3) natural heritage systems planning, (4) assessing population status, and (5) restoration of populations.     

Society and ethics - the genetics of disease

Established guidance for the protection of human subjects in research has provided the framework for research and clinical practice in genetics. Three key principles to emerge are the requirements for consent, privacy and confidentiality. However, recent research on genetic susceptibility to common diseases indicates that it may be more difficult to decide if and when genetic testing will be appropriate. Risks of disease may be low and interventions may not be available. Today, debate is primarily focussed on ethical issues raised by the use and storage of genetic information. One of the earliest experiences of genetic testing for some people is likely to be in the area of pharmacogenetics. Debate about ethical issues has been focused on the implications of patient stratification, particularly with regard to the availability of medicines for small groups and the significance of racial variation in response to medicines. The possible use of personal genetic information by insurance companies and employers has also been an issue that legislators have taken seriously.     

African and European perception of African female attractiveness

Majority of research on attractiveness is restricted to faces of European origin. The perception of attractiveness may, however, vary across communities due to variations in both facial morphology and local standards of beauty. We investigated the relative contribution of four facial markers of attractiveness based on 101 female facial portraits (standardized, non-manipulated) from Cameroon and Namibia, which were assessed by local male raters and by raters from a distant European population, the Czech Republic. Images from Cameroon include only women of Bantu origin, while Namibians are represented by women of both Bantu (Owambo/Herero) and Nama origin. While controlling for age and BMI, we explored the relationship between female attractiveness and a set of facial traits: fluctuating asymmetry, averageness, shape sexual dimorphism, and skin color (rated and measured in CIELab color space).In the Cameroonian sample, local male raters favored lighter-skinned female faces with morphology closer to average. The attractiveness of Nama women as rated by Nama men positively correlated with lighter complexion, but this did not extend to rating by Cameroonian men. The attractiveness of Namibian Owambo/Herero women was positively associated with facial femininity and lighter complexion when judged by both Cameroonian and Nama male raters. In all samples, the attractiveness as rated by Czech men was predicted by age and BMI, but not by skin color. We found no significant association between attractiveness and fluctuating asymmetry in any of the tested samples. When controlling for age, the effect of skin color on attractiveness turned to be non-significant in the Owambo/Herrero and Nama sample, but remained significant in the Cameroonian sample. Variations in skin color thus represent an important factor of African female attractiveness within the African context, but they do not seem to affect judgements made by European raters. Sensitivity to some facial markers of female attractiveness thus seems to be restricted to regional populations and/or constrained by shared ethnicity.     

Validation of a cost-efficient multi-purpose SNP panel for disease based research

Background

Here we present convergent methodologies using theoretical calculations, empirical assessment on in-house and publicly available datasets as well as in silico simulations, that validate a panel of SNPs for a variety of necessary tasks in human genetics disease research before resources are committed to larger-scale genotyping studies on those samples. While large-scale well-funded human genetic studies routinely have up to a million SNP genotypes, samples in a human genetics laboratory that are not yet part of such studies may be productively utilized in pilot projects or as part of targeted follow-up work though such smaller scale applications require at least some genome-wide genotype data for quality control purposes such as DNA “barcoding” to detect swaps or contamination issues, determining familial relationships between samples and correcting biases due to population effects such as population stratification in pilot studies.

Principal Findings

Empirical performance in classification of relative types for any two given DNA samples (e.g., full siblings, parental, etc) indicated that for outbred populations the panel performs sufficiently to classify relationship in extended families and therefore also for smaller structures such as trios and for twin zygosity testing. Additionally, familial relationships do not significantly diminish the (mean match) probability of sharing SNP genotypes in pedigrees, further indicating the uniqueness of the “barcode.” Simulation using these SNPs for an African American case-control disease association study demonstrated that population stratification, even in complex admixed samples, can be adequately corrected under a range of disease models using the SNP panel.

Conclusion

The panel has been validated for use in a variety of human disease genetics research tasks including sample barcoding, relationship verification, population substructure detection and statistical correction. Given the ease of genotyping our specific assay contained herein, this panel represents a useful and economical panel for human geneticists.     

Effect of Comprehensive Oncogenetics Training Interventions for General Practitioners,Evaluated at Multiple Performance Levels

General practitioners (GPs) are increasingly called upon to identify patients at risk for hereditary cancers, and their genetic competencies need to be enhanced. This article gives an overview of a research project on how to build effective educational modules on genetics, assessed by randomized controlled trials (RCTs), reflecting the prioritized educational needs of primary care physicians. It also reports on an ongoing study to investigate long-term increase in genetic consultation skills (1-year follow-up) and interest in and satisfaction with a supportive website on genetics among GPs. Three oncogenetics modules were developed: an online Continuing Professional Development (G-eCPD) module, a live genetic CPD module, and a “GP and genetics” website (huisartsengenetica.nl) providing further genetics information applicable in daily practice. Three assessments to evaluate the effectiveness (1-year follow-up) of the oncogenetic modules were designed: 1.An online questionnaire on self-reported genetic competencies and changes in referral behaviour, 2.Referral rates from GPs to clinical genetics centres and 3.Satisfaction questionnaire and visitor count analytics of supportive genetics website. The setting was Primary care in the Netherlands and three groups of study participants were included in the reported studies:. Assessment 1. 168 GPs responded to an email invitation and were randomly assigned to an intervention or control group, evaluating the G-eCPD module (n = 80) or the live module (n = 88). Assessment 2. Referral rates by GPs were requested from the clinical genetics centres, in the northern and southern parts of the Netherlands (Amsterdam and Maastricht), for the two years before (2010 [n = 2510] and 2011 [n = 2940]) and the year after (2012 [n = 2875]) launch of the oncogenetics CPD modules and the website. Assessment 3. Participants of the website evaluation were all recruited online. When they visited the website during the month of February 2013, a pop-up invitation came up. Of the 1350 unique visitors that month, only 38 completed the online questionnaire. Main outcomes measure showed long-term (self-reported) genetic consultation skills (i.e. increased genetics awareness and referrals to clinical genetics centres) among GPs who participated in the oncogenetic training course, and interest in and satisfaction with the supportive website. 42 GPs (52%) who previously participated in the G-eCPD evaluation study and 50 GPs (57%) who participated in the live training programme responded to the online questionnaire on long-term effects of educational outcome. Previous RCTs showed that the genetics CPD modules achieved sustained improvement of oncogenetic knowledge and consultation skills (3-months follow-up). Participants of these RCTs reported being more aware of genetic problems long term; this was reported by 29 GPs (69%) and 46 GPs (92%) participating in the G-eCPD and live module evaluation studies, respectively (Chisquare test, p<0.005). One year later, 68% of the respondents attending the live training reported that they more frequently referred patients to the clinical genetics centres, compared to 29% of those who attended the online oncogenetics training (Chisquare test, p<0.0005). However, the clinical genetics centres reported no significant change in referral numbers one year after the training. Website visitor numbers increased, as did satisfaction, reflected in a 7.7 and 8.1 (out of 10) global rating of the website (by G-eCPD and live module participants, respectively). The page most often consulted was “family tree drawing”. Self-perceived genetic consultation skills increased long-term and GPs were interested in and satisfied with the supportive website. Further studies are necessary to see whether the oncogenetics CPD modules result in more efficient referral. The results presented suggest we have provided a flexible and effective framework to meet the need for effective educational programmes for non-geneticist healthcare providers, enabling improvement of genetic medical care.     

Understanding of genetic information in higher secondary students in northeast India and the implications for genetics education

Since the work of Watson and Crick in the mid-1950s, the science of genetics has become increasingly molecular. The development of recombinant DNA technologies by the agricultural and pharmaceutical industries led to the introduction of genetically modified organisms (GMOs). By the end of the twentieth century, reports of animal cloning and recent completion of the Human Genome Project (HGP), as well techniques developed for DNA fingerprinting, gene therapy and others, raised important ethical and social issues about the applications of such technologies. For citizens to understand these issues, appropriate genetics education is needed in schools. A good foundation in genetics also requires knowledge and understanding of topics such as structure and function of cells, cell division, and reproduction. Studies at the international level report poor understanding by students of genetics and genetic technologies, with widespread misconceptions at various levels. Similar studies were nearly absent in India. In this study, I examine Indian higher secondary students' understanding of genetic information related to cells and transmission of genetic information during reproduction. Although preliminary in nature, the results provide cause for concern over the status of genetics education in India. The nature of students' conceptual understandings and possible reasons for the observed lack of understanding are discussed.     

Communication of Genetic Information within Families: The Case for Familial Comity

Advances in genetic technologies raise a multitude of ethical issues, some of which give rise to novel dilemmas for medical practice. One of the most controversial problems arising in clinical genetics is that of confidentiality and who may disclose genetic health information. This paper considers the question of when it is appropriate for health professionals to disclose clinically significant genetic information without patient consent. Existing ethical principles offer little guidance in relation to this issue. We build on suggestions that genetic information may be viewed as collective or shared information, and we introduce the concept of ‘familial comity’ as a fresh way to consider the issues.Competing Interests: None declared. Funding: No special funding was secured for this research.     

Recommendations for standardized human pedigree nomenclature. Pedigree Standardization Task Force of the National Society of Genetic Counselors.

The construction of an accurate family pedigree is a fundamental component of a clinical genetic evaluation and of human genetic research. Previous surveys of genetic counselors and human genetic publications have demonstrated significant inconsistencies in the usage of common pedigree symbols representing situations such as pregnancy, termination of pregnancy, miscarriage, and adoption, as well as less common scenarios such as pregnancies conceived through assisted reproductive technologies. The Pedigree Standardization Task Force (PSTF) was organized through the Professional Issues Committee of the National Society of Genetic Counselors, to establish recommendations for universal standards in human pedigree nomenclature. Nomenclature was chosen based on current usage, consistency among symbols, computer compatibility, and the adaptability of symbols to reflect the rapid technical advances in human genetics. Preliminary recommendations were presented for review at three national meetings of human genetic professionals and sent to > 100 human genetic professionals for review. On the basis of this review process, the recommendations of the PSTF for standardized human pedigree nomenclature are presented here. By incorporating these recommendations into medical genetics professional training programs, board examinations, genetic publications, and pedigree software, the adoption of uniform pedigree nomenclature can begin. Usage of standardized pedigree nomenclature will reduce the chances for incorrect interpretation of patient and family medical and genetic information. It may also improve the quality of patient care provided by genetic professionals and facilitate communication between researchers involved with genetic family studies.     

A multi‐perspective view of genetic variation in Cameroon

In this study, we report the genetic variation of autosomal and Y‐chromosomal microsatellites in a large Cameroon population dataset (a total of 11 populations) and jointly analyze novel and previous genetic data (mitochondrial DNA and protein coding loci) taking geographic and cultural factors into consideration. The complex pattern of genetic variation of Cameroon can in part be described by contrasting two geographic areas (corresponding to the northern and southern part of the country), which differ substantially in environmental, biological, and cultural aspects. Northern Cameroon populations show a greater within‐ and among‐group diversity, a finding that reflects the complex migratory patterns and the linguistic heterogeneity of this area. A striking reduction of Y‐chromosomal genetic diversity was observed in some populations of the northern part of the country (Podokwo and Uldeme), a result that seems to be related to their demographic history rather than to sampling issues. By exploring patterns of genetic, geographic, and linguistic variation, we detect a preferential correlation between genetics and geography for mtDNA. This finding could reflect a female matrimonial mobility that is less constrained by linguistic factors than in males. Finally, we apply the island model to mitochondrial and Y‐chromosomal data and obtain a female‐to‐male migration Nν ratio that was more than double in the northern part of the country. The combined effect of the propensity to inter‐populational admixture of females, favored by cultural contacts, and of genetic drift acting on Y‐chromosomal diversity could account for the peculiar genetic pattern observed in northern Cameroon. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.