Down syndrome in the context of "Genetic testing"

A syndrome is a set of medical signs and symptoms which are correlated with each other and often associated with a particular disease or disorder. The word derives from the Greek σύνδρομον, meaning "concurrence". When a syndrome is paired with a definite cause this becomes a disease. In some instances, a syndrome is so closely linked with a pathogenesis or cause that the words syndrome, disease, and disorder end up being used interchangeably for them. This substitution of terminology often confuses the reality and meaning of medical diagnoses. This is especially true of inherited syndromes. About one third of all phenotypes that are listed in OMIM are described as dysmorphic, which usually refers to the facial gestalt. For example, Down syndrome, Wolf–Hirschhorn syndrome, and Andersen–Tawil syndrome are disorders with known pathogeneses, so each is more than just a set of signs and symptoms, despite the syndrome nomenclature. In other instances, a syndrome is not specific to only one disease. For example, toxic shock syndrome can be caused by various toxins; another medical syndrome named as premotor syndrome can be caused by various brain lesions; and premenstrual syndrome is not a disease but simply a set of symptoms.

If an underlying genetic cause is suspected but not known, a condition may be referred to as a genetic association (often just "association" in context). By definition, an association indicates that the collection of signs and symptoms occurs in combination more frequently than would be likely by chance alone.

Special education (also known as special-needs education, aided education, alternative provision, exceptional student education, special ed., SDC, and SPED) is the practice of educating students in a way that accommodates their individual differences, disabilities, and special needs. This involves the individually planned and systematically monitored arrangement of teaching procedures, adapted equipment and materials, and accessible settings. These interventions are designed to help individuals with special needs achieve a higher level of personal self-sufficiency and success in school and in their community, which may not be available if the student were only given access to a typical classroom education.

Special education aims to provide accommodated education for students with disabilities such as learning disabilities, learning difficulties (such as dyslexia), communication disorders, emotional and behavioral disorders, physical disabilities (such as osteogenesis imperfecta, down syndrome, lissencephaly, Sanfilippo syndrome, and muscular dystrophy), developmental disabilities (such as autism spectrum disorder, and intellectual disabilities) and other disabilities. Students with disabilities are likely to benefit from additional educational services such as different approaches to teaching, the use of technology, a specifically adapted teaching area, a resource room, or a separate classroom.

Riget (English title: The Kingdom) is a Danish absurdist supernatural horror miniseries trilogy created by Lars von Trier and Tómas Gislason. Set in the neurosurgical ward of Copenhagen's Rigshospitalet (lit. 'The National Hospital', nicknamed "Riget", lit. 'the realm' or 'the kingdom'), each episode of the show follows the hospital's eccentric staff and patients as they encounter bizarre and sometimes supernatural phenomena. The series is notable for its wry humor, its muted sepia colour scheme, and the appearance of a chorus of dishwashers with Down syndrome, who discuss in intimate detail the strange occurrences in the hospital. The main theme's song was written by von Trier himself.

The first series of four episodes premiered from DR in November to December 1994, and was followed by a second series, Riget II, which aired in November 1997. A belated third and final series of five episodes, directed by von Trier and written by von Trier with Niels Vørsel, entitled Exodus, began filming in 2021 and was screened out of competition at the Venice Film Festival and at the Serial Killer festival in September 2022, and premiered on Nordic streaming platform Viaplay with the first two episodes on 9 October. The series premiered in select regions between 27 November and 25 December on streaming platform MUBI.

Intellectual disability (ID), also known as general learning disability (in the United Kingdom), and formerly mental retardation (in the United States), is a generalized neurodevelopmental disorder characterized by significant impairment in intellectual and adaptive functioning that is first apparent during childhood. Children with intellectual disabilities typically have an intelligence quotient (IQ) below 70 and deficits in at least two adaptive behaviors that affect everyday living. According to the DSM-5, intellectual functions include reasoning, problem solving, planning, abstract thinking, judgment, academic learning, and learning from experience. Deficits in these functions must be confirmed by clinical evaluation and individualized standard IQ testing. On the other hand, adaptive behaviors include the social, developmental, and practical skills people learn to perform tasks in their everyday lives. Deficits in adaptive functioning often compromise an individual's independence and ability to meet their social responsibility.

Intellectual disability is subdivided into syndromic intellectual disability, in which intellectual deficits associated with other medical and behavioral signs and symptoms are present, and non-syndromic intellectual disability, in which intellectual deficits appear without other abnormalities. Down syndrome and fragile X syndrome are examples of syndromic intellectual disabilities.

A chromosomal abnormality or chromosomal anomaly is a missing, extra, or irregular portion of chromosomal DNA. These can occur in the form of numerical abnormalities, where there is an atypical number of chromosomes, or as structural abnormalities, where one or more individual chromosomes are altered. Chromosome mutation was formerly used in a strict sense to mean a change in a chromosomal segment, involving more than one gene. Chromosome anomalies usually occur when there is an error in cell division following meiosis or mitosis. Chromosome abnormalities may be detected or confirmed by comparing an individual's karyotype, or full set of chromosomes, to a typical karyotype for the species via genetic testing.

Sometimes chromosomal abnormalities arise in the early stages of an embryo, sperm, or infant. They can be caused by various environmental factors. The implications of chromosomal abnormalities depend on the specific problem, they may have quite different ramifications. Diseases and conditions caused by chromosomal abnormalities are called chromosomal disorders or chromosomal aberrations. Some examples are Down syndrome and Turner syndrome. However, chromosomal abnormalities do not always lead to diseases. Among abnormalities, structural rearrangements of genes between chromosomes can be harmless if they are balanced, which means that a set of the chromosomes remains complete and there are no gene breaks across the chromosomes.

The development of the nervous system, or neural development (neurodevelopment), refers to the processes that generate, shape, and reshape the nervous system of animals, from the earliest stages of embryonic development to adulthood. The field of neural development draws on both neuroscience and developmental biology to describe and provide insight into the cellular and molecular mechanisms by which complex nervous systems develop, from nematodes and fruit flies to mammals.

Defects in neural development can lead to malformations such as holoprosencephaly, and a wide variety of neurological disorders including limb paresis and paralysis, balance and vision disorders, and seizures, and in humans other disorders such as Rett syndrome, Down syndrome and intellectual disability.

Aneuploidy is the presence of an abnormal number of chromosomes in a cell, for example a human somatic cell having 45 or 47 chromosomes instead of the usual 46. It does not include a difference of one or more complete sets of chromosomes. A cell with any number of complete chromosome sets is called a euploid cell.

An extra or missing chromosome is a common cause of some genetic disorders. Some cancer cells also have abnormal numbers of chromosomes. About 68% of human solid tumors are aneuploid. Aneuploidy originates during cell division when the chromosomes do not separate properly between the two cells (nondisjunction). Most cases of aneuploidy in the autosomes result in miscarriage, and the most common extra autosomal chromosomes among live births are 21, 18 and 13. Chromosome abnormalities are detected in 1 of 160 live human births. Autosomal aneuploidy is more dangerous than sex chromosome aneuploidy, as autosomal aneuploidy is almost always lethal to embryos that cease developing because of it.

Leukemia (also spelled leukaemia; pronounced /luːˈkiːmiːə/ loo-KEE-mee-ə) is a group of blood cancers that usually begin in the bone marrow and produce high numbers of abnormal blood cells. These blood cells are not fully developed and are called blasts or leukemia cells. Symptoms may include bleeding and bruising, bone pain, fatigue, fever, and an increased risk of infections. These symptoms occur due to a lack of normal blood cells. Diagnosis is typically made by blood tests or bone marrow biopsy.

The exact cause of leukemia is unknown. A combination of genetic factors and environmental (non-inherited) factors are believed to play a role. Risk factors include smoking, ionizing radiation, petrochemicals (such as benzene), prior chemotherapy, and Down syndrome. People with a family history of leukemia are also at higher risk. There are four main types of leukemia—acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL) and chronic myeloid leukemia (CML)—and a number of less common types. Leukemias and lymphomas both belong to a broader group of tumors that affect the blood, bone marrow, and lymphoid system, known as tumors of the hematopoietic and lymphoid tissues.

Clinical neuroscience is a branch of neuroscience that focuses on the scientific study of fundamental mechanisms that underlie diseases and disorders of the brain and central nervous system. It seeks to develop new ways of conceptualizing and diagnosing such disorders and ultimately of developing novel treatments.

A clinical neuroscientist is a scientist who has specialized knowledge in the field. Not all clinicians are clinical neuroscientists. Clinicians and scientists -including psychiatrists, neurologists, clinical psychologists, neuroscientists, and other specialists—use basic research findings from neuroscience in general and clinical neuroscience in particular to develop diagnostic methods and ways to prevent and treat neurobiological disorders. Such disorders include addiction, Alzheimer's disease, amyotrophic lateral sclerosis, anxiety disorders, attention deficit hyperactivity disorder, autism, bipolar disorder, brain tumors, depression, Down syndrome, dyslexia, epilepsy, Huntington's disease, multiple sclerosis, neurological AIDS, neurological trauma, pain, obsessive-compulsive disorder, Parkinson's disease, schizophrenia, sleep disorders, stroke and Tourette syndrome.