Genetic services in Chile

Demographic changes in Chile have positioned congenital malformations as a major cause of infant morbidity and mortality. At the same time, medical genetics has become increasingly important in relation to the diagnosis and management of individuals with birth defects and hereditary conditions as well as in the study of pathological pregnancies and reproductive problems. In addition, recent advances in genomic research are expanding the relevance of medical genetics to medicine as a whole. This article reviews the clinical genetic resources currently available in Chile; the teaching of genetics in undergraduate, graduate, and continued medical education; some relevant interventions that have taken place in our country, e.g. the expansion of the newborn screening program and the initiation of a folic acid fortification program, and recent efforts to enhance population access to clinical genetics services.     

Genetic services in Colombia

Medical genetic services, including clinical genetics, cytogenetics, biochemical and molecular genetics and paternity testing, are performed in Colombia in the more developed medical schools or university institutions, in nine major cities of the country. Accessibility to genetic services is limited by medical care reimbursement laws which do not cover clinical genetic services nor genetic tests. Paternity testing is performed free of charge by a governmental welfare institution, if a legal claim is made against an alleged father. Basic teaching of genetics in medical schools is mandatory, but is very uneven and limited to the better schools. Postgraduate medical genetic training is offered by four different programs of similar quality. Research is performed on some of the most prevalent genetic conditions and on population genetic issues.     

Genetic services in Ecuador

Ecuador has a population of 12 million inhabitants, composed of a variety of ethnic groups. The majority of the population lives in rural areas. There is a severe deficiency in health services, and most diseases are associated with poor life conditions: malnutrition, parasitic diseases and infections. At the same time, however, chronic diseases, e.g. cancer, have increased in prevalence. Most genetic services are provided by the private sector, which offers clinical genetic consultations and counseling, cytogenetic analyses, a limited number of molecular and biomedical tests, and prenatal diagnosis. Genetic research is centered in the universities of important cities (Quito, Guayaquil and Cuenca). The government sponsors some university research projects but does not conduct health actions in genetics in the community. There is an incipient interest in ethic and legal issues in genetics, such as how to provide modern genomic medicine in a resource-poor country.     

Community genetic services in Latin America and regional network of medical genetics. Recommendations of a World Health Organization consultation

The World Health Organization sponsored a Consultation on Community Genetic Services and a Regional Network of Medical Genetics in Latin America in Porto Alegre, Brazil, on June 19, 2003. The main recommendations of the meeting included: (a) the call for government funding of services, research and education in medical genetics; (b) the conduct of epidemiological research on the prevalence and types of birth defects, genetic disorders and genetic predispositions to common diseases; (c) the education of health professionals in genetics; (d) the education of genetic professionals in community health and public health genetics; (e) the fostering of interactions between clinical geneticists, public health personnel, primary health care workers and community organizations, and (f) a better planning of regionalized services to avoid duplication and inefficiency.     

Genetic services in Mexico City

In the year 2002, the population of Mexico was approaching 103 million inhabitants. Approximately 74% of them live in the cities with a continuous migration from rural to urban areas. Genetic departments are concentrated in the capital and other big cities. In this paper we review the current status of genetic departments in Mexico City, emphasizing the main areas of genetic services offered to the public and involved in research. We also comment on the deficiencies identified and suggest recommendations to improve the quality of the genetic services offered to the Mexican population.     

The role of the World Health Organization in promoting medical genetics in Latin America

The Human Genetics Program of the World Health Organization (WHO) has analyzed the needs for genetic services worldwide and the promotion of genetic approaches for the prevention of diseases linked to primary health care. This article presents a summary of the most important initiatives of the WHO in this field, which have served as a background for the Consultation in Medical Genetics in Latin America, which took place in Porto Alegre, Brazil, in June 19, 2003, and whose working reports are published in this special issue of Community Genetics.     

Genetic services to the latino population in the United States

In 1998 Latinos (Hispanics) in the United States number 30 million persons and account for 11.3% of the total population, while it is predicted that by the year 2020 they will become the largest minority. This article describes the demographics and health profile of the Latino population in the United States. A brief account is given of common cultural traditions and health beliefs that modulate the interaction of this population with the health delivery system in general, and that of genetic services in particular. Further, some problems in the access to, and utilization of genetic services are outlined, and the experience of a project designed to overcome those problems in New York City is described.     

Genetic services in the new era: Native American perspectives

American Indians have arrived at a critical point in their more than 500-year history with the United States Government. With the advent of the new bio-revolution, a number of tribes have voiced vehement opposition to genetic patenting, creation of cell lines, transgenic experimentation and cloning. While many are opposed to the Human Genome Diversity Project, Human Genome Project and diversity research currently being conducted by the Indian Health Service, a few embrace the beneficial aspects of biomedical/biogenetic research. Moreover, an increasing number of Indians see the need for and are seeking genetic counseling and other services. This paper briefly describes some of the issues associated with developing and implementing effective genetic services within Native American communities. Problems of access, perception of services, previous experience with genetics and cultural and other barriers are discussed. Recommendations also are rendered to assist health professionals in the development of services.     

Genetic services and research in the state of Minas Gerais, Brazil

The state of Minas Gerais in Brazil has a surface of 586,528 km(2), and 18 million inhabitants. Infant mortality rate is 20/1,000, and congenital anomalies are its second cause. There are 11 medical schools where basic genetics, but not clinical genetics, is taught. Genetic services in the state include: newborn screening for hypothyroidism, phenylketonuria, sickle cell disease and cystic fibrosis; clinical-genetic diagnostic evaluation and counseling; prenatal diagnosis, fetal medicine and paternity testing. Medical genetic services and research are underdeveloped because of limitations such as lack of health policies in genetics, small number of trained specialists, little knowledge about genetics among health professionals and low reimbursement rates.     

Experimental-mechanics services

Experimental Techniques -     

Design and application of an S-box using complete Latin square

Since a substitution box (S-box) is the nonlinearity part of a symmetric key encryption scheme, it directly determines the performance and security level of the encryption scheme. Thus, generating S-box with high performance and efficiency is attracting. This paper proposes a novel method to construct S-box using the complete Latin square and chaotic system. First, a complete Latin square is generated using the chaotic sequences produced by a chaotic system. Then an S-box is constructed using the complete Latin square. Performance analyses show that the S-box generated by our proposed method has a high performance and can achieve strong ability to resist many security attacks such as the linear attack, differential attack and so on. To show the efficiency of the constructed S-box, this paper further applies the S-box to image encryption application. Security analyses show that the developed image encryption algorithm is able to encrypt different kinds of images into cipher images with uniformly distributed histograms. Performance evaluations demonstrate that it has a high security level and can outperform several state-of-the-art encryption algorithms.

     

Genetic disorders in haematological practice in India

Haemoglobinopathies represent a significant national health burden in India. The distribution of specific disorders varies geographically and by community. Heterozygote frequencies of beta-thalassaemia range from 1 to 15%, resulting in an estimated 20 million carriers. HbS is mainly present in tribal and non-caste communities, with carrier prevalences of up to 40%. By comparison, alpha-thalassaemia carriers are found in both the caste and tribal communities, and can reach a frequency of >90% in the latter case. Community control of haemoglobinopathies relies mainly on out-reach education programmes and genetic counselling, with antenatal diagnosis offered in specific major centres. Only partial data are available on the prevalence of haemophilia, but it has been estimated that there are some 50,000 affected individuals nationwide, with an additional 1,500 new cases born each year. RFLP-based techniques have been established to detect mutations in the factor VIII and IX genes, enabling the limited introduction of carrier detection and antenatal diagnosis.     

Genetic variation in the response to vaccination

Vaccines are the most powerful means to prevent and diminish the burden of infectious disease. However, there are limitations to their use: vaccines are not yet available for all infectious diseases (including human immunodeficiency virus and respiratory syncytial virus), they sometimes lack efficacy, the response to vaccination is limited by maternal antibodies in very young infants, and the response to vaccination is variable or may even be absent in some individuals. This review focuses on genetic factors that determine the variable response to vaccination. The highly polymorphic human leukocyte antigen system, which is involved in antigen presentation, has been researched most in this aspect, and clearly affects the response to vaccination. Other, but less polymorphic pathways involved are the Toll-like receptor pathway, which is involved in antigen recognition and stimulation of the immune system, and the cytokine immunoregulatory network. The heritability, or the proportion of total variance that is due to additive genetic factors, appears to be particularly large for vaccine-induced antibody responses in young infants compared with cell-mediated responses and antibody responses in older, immunologically more mature individuals. Both antibody and cell-mediated responses are not only affected by loci within, but also strongly by loci outside the human leukocyte antigen system. Because most genes that are important in influencing immune responses to vaccination are still unknown, clearly more work is required. A better understanding of the factors that determine an effective response to vaccination may lead to the identification of specific genes and pathways as targets for the development of novel more uniformly effective vaccines.     

Medical genetics services in the city of Sao Paulo, Brazil

The city of Sao Paulo is located in the center of a metropolitan area with nearly 18 million inhabitants and 300,000 births/year. The currently existing medical genetics services are unable to meet the demand, due to their insufficient physical and personnel infrastructure. Institutions and experts in medical genetics could give short training and refresher courses to health professionals to enable them to work in the public health network. The city has a reasonably well developed health care network, represented by the Single Health System (Sistema Unico de Saude - SUS) and by the Family Health Program (Programa de Saude da Familia - PSF). The financial resources for such actions originate in the budget of the managing agencies of such systems. The limitations of genetic services provided to the population of the city could be overcome in a short period of time by developing programs within the public health care network. The city has institutions, professionals and financial resources to make this project feasible. To that end, the competent authorities of the Sao Paulo State and City Secretariats of Health should take managerial responsibility for the genetic services in the city.     

Role of primary care providers in the delivery of genetics services

Fruits of the Human Genome Project are already transforming health care. Primary care providers, regardless of specialty, will need to integrate new genetics knowledge into routine practice in order to fulfill their role in genetics services delivery. Unfortunately, few are prepared for this revolution, and current educational efforts are inadequate. To effect the changes that are needed, we must teach genetics as an integrative discipline at all stages of professional education and emphasize the value of this knowledge to practice.     

The role of voluntary consumer organisations in genetic services in the United kingdom

This article describes the role of the Genetic Interest Group (GIG), a UK alliance of charities and voluntary groups for families affected by specific genetic disorders, as an advocate for the needs of patients and their families and as an agent of change in the development of genetic services in the UK. GIG now interacts with a wide range of audiences - lay groups, the professional community, policy makers, government and the media - in a variety of different ways, so that the perspective of the 'end user' is reflected in decisions about the application of the new genetics in the field of human health.     

自适应免疫遗传算法

遗传算法(GA)是基于自然遗传规则随机搜索技术的一种进化算法,但是随着实际结构的大型化和复杂化,它往往出现过早收敛的现象。在研究了算法的编码方式、控制参数和算子操作之后,就其全局收敛性的不足,提出动态自适应策略以改进其性能,在基本遗传算子的基础上,采用了免疫遗传算子和保优策略。其中免疫算子可以防止交叉变异中的个体退化,自适应策略则保持了种群的多样性,以此保证遗传算法尽快收敛到全局最优解,称之为自适应免疫遗传算法(AIGA)。随后以经典的十杆桁架结构优化问题作为例子说明算法的优越性,结果表明AIGA在随机结构优化中计算有效、结果可靠。