Genetics

The scientific study of heredity. Genetics pertains to humans and all other organisms. So, for example, there is human genetics, mouse genetics, fruitfly genetics, etc. Human genetics today comprises a number of overlapping fields, including: {{}}Classical or formal genetics — the study of the transmission of single genes within families and the analysis of more complex types of inheritance. Clinical genetics — the diagnosis, prognosis and, in some cases, the treatment of genetic diseases. Genetic counseling — an important area within clinical genetics involving the diagnosis, risk assessment, and interpersonal communication. Cytogenetics — the study of chromosomes in health and disease. Biochemical genetics — the biochemistry of nucleic acids and proteins including enzymes. Pharmacogenetics — how genes govern the absorption, metabolism and disposal of drugs and untoward reactions to them. Molecular genetics — the molecular study of genetics including particularly DNA and RNA. Immunogenetics — the genetics of the immune system including blood groups, HLA, and the immunoglobulins. Behavioral genetics — the study of genetic factors in behavior in health and disease including mental retardation and mental illness. Population genetics — the study of genes within populations including gene frequencies, the gene pool, and evolution. Reproductive genetics — the genetics of reproduction including genes and chromosomes in germ cells and the early embryo. Developmental genetics — the genetics of normal and abnormal development including congenital malformations (birth defects). Ecogenetics — the interaction of genetics with the environment. Forensic genetics — the application of genetic knowledge, including DNA, to legal matters.

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1. The branch of science concerned with the means and consequences of transmission and generation of the components of biologic inheritance. 2. The genetic features and constitution of any single organism or set of organisms. [G. genesis, origin or production]

- behavioral g. the study of heritable factors in behavioral patterns, as by pedigree analysis, biochemical abnormality, or karyotypic analysis.

- biochemical g. the study of g. in terms of the chemical (biochemical) events involved, as in the manner in which DNA molecules replicate and control the synthesis of specific enzymes by the genetic code.

- classical g. that body of method and analysis that perceives g. as the study of the transmission of genotype from parent to offspring; the study of multiple individuals is essential to it.

- clinical g. g. applied to the diagnosis, prognosis, management, and prevention of genetic diseases. Cf.:medical g..

- epidemiologic g. the study of g. as a phenomenon of defined populations by the criteria, methods, and objectives of epidemiology rather than of population g..

- galtonian g. the study of traits by analysis of the first two moments of metrical data; the preferred method for analysis of traits following the multivariate gaussian distribution.

- Galtonian-Fisher g. the g. of measurable traits determined by multiple loci which make contributions that are independent, additive, and approximately equal. SYN: multilocal g..

- human g. the study of the genetic aspects of humans as a species. Cf.:medical g..

- mathematical g. the study of genetic traits by formal analysis, e.g., quantitative g., population dynamics, genetic epidemiology, modeling.

- medical g. the study of the etiology, pathogenesis, and natural history of human diseases which are at least partially genetic in origin. Cf.:clinical g., human g..

- mendelian g. the study of the pattern of segregation of phenotypes under the control of genetic loci taken one at a time.

- microbial g. the study of hereditary mechanisms of microbes.

- modern g. that body of method and analysis that perceives g. as the study of the economy of nucleic acid s and associated compounds.

- molecular g. molecular biology applied to g..

- multilocal g. SYN: Galtonian-Fisher g..

- population g. the study of genetic influences on the components of cause and effect in the somatic characteristics of populations.

- quantitative g. the formal study of measurable genetic traits, traditionally but not necessarily confined to galtonian g..

- reverse g. term referring to tracing of a gene responsible for a disease by learning its position in the human genome. This approach makes no claim of providing information about the gene product. SYN: positional cloning.

- somatic cell g. the study of the structure, organization, and function of a genome by the techniques of cell hybridization.

- statistical g. the study of the applications of principles of statistics to problems in g..

- transplantation g. g. as applied to the transplanting of tissues from one animal to another.

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ge·net·ics jə-'net-iks n pl but sing in constr

1 a) a branch of biology that deals with the heredity and variation of organisms

b) a treatise or textbook on genetics

2) the genetic makeup and phenomena of an organism, type, group, or condition

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n.

the science of inheritance. It attempts to explain the differences and similarities between related organisms and the ways in which characters are passed from parents to their offspring. Human and medical genetics are concerned with the study of inherited diseases. See also cytogenetics, Mendel's laws.

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ge·net·ics (jə-netґiks) [Gr. gennan to produce] the study of genes and their heredity.