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Propositus
In medical genetics and other medical fields, a proband, propositus (male proband), or proposita (female proband) is a particular subject (human or other animal) being studied or reported on. On pedigrees, the proband is noted with a square (male) or circle (female) shaded accordingly. Denoting the proband is important, so the relationship to other individuals can be seen and patterns established. In most cases, the proband is the first affected family member who seeks medical attention for a genetic disorder. Among the ancestors of the proband, other subjects may manifest the disease, but the proband typically refers to the member seeking medical attention or being studied, even if affected ancestors are known. Often, affected ancestors are unknown due to the lack of information regarding those individuals or about the disease at the time they lived. Other ancestors might be undiagnosed due to the incomplete penetrance or variable expressivity. The diagnosis of a proband raises ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Genetics
Medical genetics is the branch of medicine that involves the diagnosis and management of hereditary disorders. Medical genetics differs from human genetics in that human genetics is a field of scientific research that may or may not apply to medicine, while medical genetics refers to the application of genetics to medical care. For example, research on the causes and inheritance of genetic disorders would be considered within both human genetics and medical genetics, while the diagnosis, management, and counselling people with genetic disorders would be considered part of medical genetics. In contrast, the study of typically non-medical phenotypes such as the genetics of eye color would be considered part of human genetics, but not necessarily relevant to medical genetics (except in situations such as albinism). ''Genetic medicine'' is a newer term for medical genetics and incorporates areas such as gene therapy, personalized medicine, and the rapidly emerging new medical specia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Institutes Of Health
The National Institutes of Health (NIH) is the primary agency of the United States government responsible for biomedical and public health research. It was founded in 1887 and is part of the United States Department of Health and Human Services (HHS). Many NIH facilities are located in Bethesda, Maryland, and other nearby suburbs of the Washington metropolitan area, with other primary facilities in the Research Triangle Park in North Carolina and smaller satellite facilities located around the United States. The NIH conducts its scientific research through the NIH Intramural Research Program (IRP) and provides significant biomedical research funding to non-NIH research facilities through its Extramural Research Program. , the IRP had 1,200 principal investigators and more than 4,000 postdoctoral fellows in basic, translational, and clinical research, being the largest biomedical research institution in the world, while, as of 2003, the extramural arm provided 28% of biomedical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pedigree Chart
A pedigree chart is a diagram that shows the occurrence of certain traits through different generations of a family, most commonly for humans, show dogs, and race horses. Definition The word pedigree is a corruption of the Anglo-Norman French ''pé de grue'' or "crane's foot", either because the typical lines and split lines (each split leading to different offspring of the one parent line) resemble the thin leg and foot of a Crane (bird), crane or because such a mark was used to denote succession in pedigree charts. A pedigree results in the presentation of family information in the form of an easily readable chart. It can be simply called a "family tree". Pedigrees use a standardized set of symbols, squares represent males and circles represent females. Pedigree construction is a family history, and details about an earlier generation may be uncertain as memories fade. If the sex of the person is unknown, a diamond is used. Someone with the phenotype (trait) in question is repre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Disorder
A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosome abnormality. Although polygenic disorders are the most common, the term is mostly used when discussing disorders with a single genetic cause, either in a gene or chromosome. The mutation responsible can occur spontaneously before embryonic development (a ''de novo'' mutation), or it can be inherited from two parents who are carriers of a faulty gene ( autosomal recessive inheritance) or from a parent with the disorder (autosomal dominant inheritance). When the genetic disorder is inherited from one or both parents, it is also classified as a hereditary disease. Some disorders are caused by a mutation on the X chromosome and have X-linked inheritance. Very few disorders are inherited on the Y chromosome or mitochondrial DNA (due to their size). There are well over 6,000 known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancestor
An ancestor, also known as a forefather, fore-elder, or a forebear, is a parent or ( recursively) the parent of an antecedent (i.e., a grandparent, great-grandparent, great-great-grandparent and so forth). ''Ancestor'' is "any person from whom one is descended. In law, the person from whom an estate has been inherited." Relationship Two individuals have a genetic relationship if one is the ancestor of the other or if they share a common ancestor. In evolutionary theory, species which share an evolutionary ancestor are said to be of common descent. However, this concept of ancestry does not apply to some bacteria and other organisms capable of horizontal gene transfer. Some research suggests that the average person has twice as many female ancestors as male ancestors. This might have been due to the past prevalence of polygynous relations and female hypergamy. Assuming that all of an individual's ancestors are otherwise unrelated to each other, that individual has 2'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penetrance
Penetrance in genetics is the proportion of individuals carrying a particular variant (or allele) of a gene (genotype) that also expresses an associated trait (phenotype). In medical genetics, the penetrance of a disease-causing mutation is the proportion of individuals with the mutation that exhibit clinical Symptom, symptoms among all individuals with such mutation. For example: If a mutation in the gene responsible for a particular autosomal dominant disorder has 95% penetrance, then 95% of those with the mutation will go on to develop the disease, showing its phenotype, whereas 5% will not. Penetrance only refers to whether an individual with a specific genotype exhibits any phenotypic signs or symptoms, and is not to be confused with Expressivity (genetics), variable expressivity which is to what extent or degree the symptoms for said disease are shown (the expression of the phenotypic trait). Meaning that, even if the same disease-causing mutation affects separate individ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expressivity (genetics)
In genetics, expressivity is the degree to which a phenotype is expressed by individuals having a particular genotype. Alternatively, it may refer to the expression of a particular gene by individuals having a certain phenotype. Expressivity is related to the ''intensity'' of a given phenotype; it differs from penetrance, which refers to the ''proportion'' of individuals with a particular genotype that share the same phenotype. Variable expressivity Variable expressivity refers to the phenomenon by which individuals with a shared genotype exhibit varying phenotypes. This can be further described as a spectrum of associated traits that can range in size, colour, intensity, and so forth. Variable expressivity can be seen in plants and animals, such as differences in hair colour, leaf size, and severity of diseases. Mechanisms influencing expressivity This variation in expression can be affected by modifier genes, epigenetic factors or the environment. # Modifier genes can a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Diagnosis
Medical diagnosis (abbreviated Dx, Dx, or Ds) is the process of determining which disease or condition explains a person's symptoms and signs. It is most often referred to as a diagnosis with the medical context being implicit. The information required for a diagnosis is typically collected from a history and physical examination of the person seeking medical care. Often, one or more diagnostic procedures, such as medical tests, are also done during the process. Sometimes the posthumous diagnosis is considered a kind of medical diagnosis. Diagnosis is often challenging because many signs and symptoms are nonspecific. For example, redness of the skin ( erythema), by itself, is a sign of many disorders and thus does not tell the healthcare professional what is wrong. Thus differential diagnosis, in which several possible explanations are compared and contrasted, must be performed. This involves the correlation of various pieces of information followed by the recognition and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genealogy
Genealogy () is the study of families, family history, and the tracing of their lineages. Genealogists use oral interviews, historical records, genetic analysis, and other records to obtain information about a family and to demonstrate kinship and pedigrees of its members. The results are often displayed in charts or written as narratives. The field of family history is broader than genealogy, and covers not just lineage but also family and community history and biography. The record of genealogical work may be presented as a "genealogy", a "family history", or a " family tree". In the narrow sense, a "genealogy" or a " family tree" traces the descendants of one person, whereas a "family history" traces the ancestors of one person, but the terms are often used interchangeably. A family history may include additional biographical information, family traditions, and the like. The pursuit of family history and origins tends to be shaped by several motives, including the des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ahnentafel
An ''ahnentafel'' ( German for "ancestor table"; ) or ''ahnenreihe'' ("ancestor series"; ) is a genealogical numbering system for listing a person's direct ancestors in a fixed sequence of ascent. The subject (or proband) of the ahnentafel is listed as , the subject's father as and the mother as , the paternal grandparents as and and the maternal grandparents as and , and so on, back through the generations. Apart from , who can be male or female, all even-numbered persons are male, and all odd-numbered persons are female. In this schema, the number of any person's father is double the person's number, and a person's mother is double the person's number plus one. Using this definition of numeration, one can derive some basic information about individuals who are listed without additional research. This construct displays a person's genealogy compactly, without the need for a diagram such as a family tree. It is particularly useful in situations where one may be restricted t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progenitor
In genealogy, a progenitor (rarer: primogenitor; or ''Ahnherr'') is the founder (sometimes one that is legendary) of a family, line of descent, gens, clan, tribe, noble house, or ethnic group.. Ebenda''Ahnherr:''"Stammvater eines Geschlechts". Genealogy (commonly known as family history) understands a progenitor to be the earliest recorded ancestor of a consanguineous family group of descendants. Progenitors are sometimes used to describe the status of a genealogical research project, or in order to compare the availability of genealogical data in different times and places. Often, progenitors are implied to be patrilineal. If a patrilineal dynasty is considered, each such dynasty has exactly one progenitor. Aristocratic and dynastic families often look back to an ancestor who is seen as the founder and progenitor of their house (i.e. family line). Even the old Roman legal concept of agnates (Latin for "descendants") was based on the idea of the unbroken family lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trial By Ordeal
Trial by ordeal was an ancient judicial practice by which the guilt or innocence of the accused (called a "proband") was determined by subjecting them to a painful, or at least an unpleasant, usually dangerous experience. In medieval Europe, like trial by combat, trial by ordeal, such as cruentation, was sometimes considered a "judgement of God" (, ): a procedure based on the premise that God would help the innocent by performing a miracle on their behalf. The practice has much earlier roots, attested to as far back as the Code of Hammurabi and the Code of Ur-Nammu. In pre-industrial society, the ordeal typically ranked along with the oath and witness accounts as the central means by which to reach a judicial verdict. Indeed, the term ''ordeal'', Old English ''ordǣl'', has the meaning of "judgment, verdict" from Proto-West Germanic uʀdailī (see , ), ultimately from Proto-Germanic ''*uzdailiją'' "that which is dealt out". Priestly cooperation in trials by fire and water w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
