American Native Continental Ancestry Group: Individuals whose ancestral origins are in the continents of the Americas.African Continental Ancestry Group: Individuals whose ancestral origins are in the continent of Africa.European Continental Ancestry Group: Individuals whose ancestral origins are in the continent of Europe.Asian Continental Ancestry Group: Individuals whose ancestral origins are in the southeastern and eastern areas of the Asian continent.African Americans: Persons living in the United States having origins in any of the black groups of Africa.Oceanic Ancestry Group: Individuals whose ancestral origins are in the islands of the central and South Pacific, including Micronesia, Melanesia, Polynesia, and traditionally Australasia.Genealogy and HeraldryAfricaPolymorphism, Single Nucleotide: A single nucleotide variation in a genetic sequence that occurs at appreciable frequency in the population.Genetics, Population: The discipline studying genetic composition of populations and effects of factors such as GENETIC SELECTION, population size, MUTATION, migration, and GENETIC DRIFT on the frequencies of various GENOTYPES and PHENOTYPES using a variety of GENETIC TECHNIQUES.Trypanosomiasis, African: A disease endemic among people and animals in Central Africa. It is caused by various species of trypanosomes, particularly T. gambiense and T. rhodesiense. Its second host is the TSETSE FLY. Involvement of the central nervous system produces "African sleeping sickness." Nagana is a rapidly fatal trypanosomiasis of horses and other animals.Genotype: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.Genome-Wide Association Study: An analysis comparing the allele frequencies of all available (or a whole GENOME representative set of) polymorphic markers in unrelated patients with a specific symptom or disease condition, and those of healthy controls to identify markers associated with a specific disease or condition.South Africa: A republic in southern Africa, the southernmost part of Africa. It has three capitals: Pretoria (administrative), Cape Town (legislative), and Bloemfontein (judicial). Officially the Republic of South Africa since 1960, it was called the Union of South Africa 1910-1960.Haplotypes: The genetic constitution of individuals with respect to one member of a pair of allelic genes, or sets of genes that are closely linked and tend to be inherited together such as those of the MAJOR HISTOCOMPATIBILITY COMPLEX.Central African Republic: A republic in central Africa south of CHAD and SUDAN, north of DEMOCRATIC REPUBLIC OF THE CONGO, and east of CAMEROON. The capital is Bangui.Gene Frequency: The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.Genetic Variation: Genotypic differences observed among individuals in a population.Gene Pool: The total genetic information possessed by the reproductive members of a POPULATION of sexually reproducing organisms.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Genetic Predisposition to Disease: A latent susceptibility to disease at the genetic level, which may be activated under certain conditions.Indians, South American: Individual members of South American ethnic groups with historic ancestral origins in Asia.African Swine Fever Virus: The lone species of the genus Asfivirus. It infects domestic and wild pigs, warthogs, and bushpigs. Disease is endemic in domestic swine in many African countries and Sardinia. Soft ticks of the genus Ornithodoros are also infected and act as vectors.Ethnic Groups: A group of people with a common cultural heritage that sets them apart from others in a variety of social relationships.Trinidad and Tobago: An independent state in the Lesser Antilles in the West Indies, north of Venezuela, comprising the islands of Trinidad and Tobago. Its capital is Port of Spain. Both islands were discovered by Columbus in 1498. The Spanish, English, Dutch, and French figure in their history over four centuries. Trinidad and Tobago united in 1898 and were made part of the British colony of Trinidad and Tobago in 1899. The colony became an independent state in 1962. Trinidad was so named by Columbus either because he arrived on Trinity Sunday or because three mountain peaks suggested the Holy Trinity. Tobago was given the name by Columbus from the Haitian tambaku, pipe, from the natives' habit of smoking tobacco leaves. (Webster's New Geographical Dictionary, 1988, p1228, 1216 & Room, Brewer's Dictionary of Names, 1992, p555, 547)Hispanic Americans: Persons living in the United States of Mexican (MEXICAN AMERICANS), Puerto Rican, Cuban, Central or South American, or other Spanish culture or origin. The concept does not include Brazilian Americans or Portuguese Americans.Africa, Western: The geographical area of Africa comprising BENIN; BURKINA FASO; COTE D'IVOIRE; GAMBIA; GHANA; GUINEA; GUINEA-BISSAU; LIBERIA; MALI; MAURITANIA; NIGER; NIGERIA; SENEGAL; SIERRA LEONE; and TOGO.Genetic Loci: Specific regions that are mapped within a GENOME. Genetic loci are usually identified with a shorthand notation that indicates the chromosome number and the position of a specific band along the P or Q arm of the chromosome where they are found. For example the locus 6p21 is found within band 21 of the P-arm of CHROMOSOME 6. Many well known genetic loci are also known by common names that are associated with a genetic function or HEREDITARY DISEASE.Linkage Disequilibrium: Nonrandom association of linked genes. This is the tendency of the alleles of two separate but already linked loci to be found together more frequently than would be expected by chance alone.Alleles: Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.African Swine Fever: A sometimes fatal ASFIVIRUS infection of pigs, characterized by fever, cough, diarrhea, hemorrhagic lymph nodes, and edema of the gallbladder. It is transmitted between domestic swine by direct contact, ingestion of infected meat, or fomites, or mechanically by biting flies or soft ticks (genus Ornithodoros).Genome, Human: The complete genetic complement contained in the DNA of a set of CHROMOSOMES in a HUMAN. The length of the human genome is about 3 billion base pairs.Patient Handoff: The transferring of patient care responsibility from one health-care professional to another.Medical Subject Headings: Controlled vocabulary thesaurus produced by the NATIONAL LIBRARY OF MEDICINE. It consists of sets of terms naming descriptors in a hierarchical structure that permits searching at various levels of specificity.MEDLINE: The premier bibliographic database of the NATIONAL LIBRARY OF MEDICINE. MEDLINE® (MEDLARS Online) is the primary subset of PUBMED and can be searched on NLM's Web site in PubMed or the NLM Gateway. MEDLINE references are indexed with MEDICAL SUBJECT HEADINGS (MeSH).PubMed: A bibliographic database that includes MEDLINE as its primary subset. It is produced by the National Center for Biotechnology Information (NCBI), part of the NATIONAL LIBRARY OF MEDICINE. PubMed, which is searchable through NLM's Web site, also includes access to additional citations to selected life sciences journals not in MEDLINE, and links to other resources such as the full-text of articles at participating publishers' Web sites, NCBI's molecular biology databases, and PubMed Central.Information Storage and Retrieval: Organized activities related to the storage, location, search, and retrieval of information.Abstracting and Indexing as Topic: Activities performed to identify concepts and aspects of published information and research reports.Subject Headings: Terms or expressions which provide the major means of access by subject to the bibliographic unit.Child Abuse: Abuse of children in a family, institutional, or other setting. (APA, Thesaurus of Psychological Index Terms, 1994)Child Welfare: Organized efforts by communities or organizations to improve the health and well-being of the child.Foster Home Care: Families who care for neglected children or patients unable to care for themselves.Mandatory Reporting: A legal requirement that designated types of information acquired by professionals or institutions in the course of their work be reported to appropriate authorities.Social Work: The use of community resources, individual case work, or group work to promote the adaptive capacities of individuals in relation to their social and economic environments. It includes social service agencies.Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.Caregivers: Persons who provide care to those who need supervision or assistance in illness or disability. They may provide the care in the home, in a hospital, or in an institution. Although caregivers include trained medical, nursing, and other health personnel, the concept also refers to parents, spouses, or other family members, friends, members of the clergy, teachers, social workers, fellow patients.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Latin America: The geographic area of Latin America in general and when the specific country or countries are not indicated. It usually includes Central America, South America, Mexico, and the islands of the Caribbean.BooksPublishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.Serial Publications: Publications in any medium issued in successive parts bearing numerical or chronological designations and intended to be continued indefinitely. (ALA Glossary of Library and Information Science, 1983, p203)