A measure of the degree to which a characteristic is related to genetic, inherited factors is called
Introduction[edit | edit source] Show
A genetic disorder is a disease caused in whole or in part by a change in the DNA sequence away from the normal sequence. An x-shaped chromosome is made up of tightly wound strands of DNA. DNA has smaller sections, called genes, which can "code" for physical traits. The Gene is the basic physical unit of inheritance.
Chromosomes contains the DNA in a form coiled with histone proteins condensing it. Genetic disorders can be caused by
New discoveries of the human genome (the complete set of human genes) find that nearly all diseases have a genetic component.
For a great introduction and visualisation about inheritance see below History[edit | edit source]Genetics as a scientific discipline stemmed from the work of Gregor Mendel in the middle of the 19th century. Mendel suspected that traits were inherited as discrete units, and, although he knew nothing of the physical or chemical nature of genes at the time, his units became the basis for the development of the present understanding of heredity. All present research in genetics can be traced back to Mendel’s discovery of the laws governing the inheritance of traits.[2] Difference Between Genetic and Hereditary Diseases[edit | edit source]
Gene Editing[edit | edit source]DNA repair after CRISPR-Cas9 double strand break CRISPR is a type of gene-editing technology that lets scientists more rapidly and accurately 'cut' and 'paste' genes into DNA. It is based on a targeted DNA-destroying defence system originally found in certain prokaryotes.
Genetic inheritance pathways[edit | edit source]Genetic abnormalities can be inherited through different pathways, depending on the location and type of the affected gene. The three types of inheritance for monogenic (single-gene) diseases are[5]:
The Punnet Square: Used to determine the possible outcomes of traits being transferred from the parents to the offspring. Animation of the structure of a section of DNA shown on R. The bases lie horizontally between the two spiraling strands. Nitrogen: blue, Oxygen: red, carbon: green, hydrogen: white, phosphorous: orange Diagnosis[edit | edit source]Genetic testing is one of several tools that doctors use to diagnose genetic conditions. The approaches to making a genetic diagnosis include:
Most common disorders[edit | edit source]Monogenic diseases[5]:
Polygenic conditions[7]:
Others:
Treatment[edit | edit source]The treatment of conditions arising from genetic abnormalities are as variant as the conditions can be. They depend very much on the area of the body that is affected by the disease. To see specifics about physiotherapy treatment of common genetic conditions, please check the above listed diseases for further information. See also CRISPR above Definitions[edit | edit source]
Useful links[edit | edit source]Physiopedia page: Congenital and Acquired Neuromuscular and Genetic Disorders. References[edit | edit source]
What is a characteristic that is inherited called?Heredity is a process in which organisms acquire characteristics from their parents. These characteristics are called traits.
What is a heritability coefficient?Calculating Heritability
Broad-sense heritability is represented as H2 and indicates all the genetic factors that go into phenotypic variance in a population. It can be calculated as: H2 = Var(G) / Var(P). This is where Var(G) is the variance in genotype and Var(P) is the variance in phenotype in a population.
What are the genetic factors that affect the genes?Various factors, including genetic makeup, exposure to harmful substances, other environmental influences, and age, can affect expressivity. Both penetrance and expressivity can vary: People with the gene may or may not have the trait and, in people with the trait, how the trait is expressed can vary.
What is meant by heritability?Listen to pronunciation. (HAYR-ih-tuh-BIH-lih-tee) The proportion of variation in a population trait that can be attributed to inherited genetic factors. Heritability estimates range from 0 to 1 and are often expressed as a percentage.
|