Recessive

Recessive

In genetics, a recessive gene is an allele that causes a phenotype (visible or detectable characteristic) that is only seen in a homozygous genotype (an organism that has two copies of the same allele) and never in a heterozygous genotype. Every person has two copies of every gene on autosomal chromosomes, one from mother and one from father. If a genetic trait is recessive, a person needs to inherit two copies of the gene for the trait to be expressed. Thus, both parents have to be carriers of a recessive trait in order for a child to express that trait. Note that "expression" in this sense does not refer to genetic expression (i.e., transcription and translation) of the gene. Instead, "expression" here refers to the observance of the gene within the phenotype. If both parents are carriers, there is a 25% chance with each child to show the recessive trait in the phenotype. Thus if the parents are closely related (in-breeding) the probability of both having inherited the same gene is increased and as a result the probability of the children showing the recessive trait is increased as well.

The term "recessive gene" is part of the laws of Mendelian inheritance created by Gregor Mendel. Examples of recessive genes in Mendel's famous pea plant experiments include those that determine the color and shape of seed pods, and plant height.

Read more about Recessive:  Allosomal Recessive Gene, Autosomal Recessive Gene, Nomenclature

Other articles related to "recessive":

Autosomal Recessive Polycystic Kidney
... The recessive form of polycystic kidney, called ARPKD (autosomal recessive polycystic kidney disease) is less common than autosomal dominant polycystic kidney ...
List Of Mendelian Traits In Humans - Examples
... dominant) Ability to smell (bitter almond-like) hydrogen cyanide (recessive) Albinism (recessive) Brachydactyly (shortness of fingers and toes) Wet (dominant) or dry (recessive ...
Pseudodominance
... Pseudodominance is the situation in which the inheritance of an autosomal recessive trait mimics an autosomal dominant pattern ... The pattern of inheritance in which the recessive allele could give its expression in absence of its dominant allele is known as pseudodominance ... are the genetic disease due to X linked recessive allele giving their expression in human male is pseudodominance and in human female is dominance ...
Examples - Autosomal Recessive Disease
... associated with the sickle genotype - anemia (a recessive trait) blood cell sickling (co-dominant) altered beta-globin electrophoretic mobility (co-dominant) resistance to malaria ... Other recessive disorders Cystic fibrosis PKAN/NBIA Tay-Sachs disease Chronic granulomatous disease Thalassemia Bloom's Syndrome Alpha 1-antitrypsin deficiency ...
Longhaired Whippet - Health
... the intense inbreeding necessary to select for a recessive trait such as long hair can concurrently select for other undesirable recessive traits, especially those that are (by chance) linked to the ... Longhaired Whippets are potential carriers of a recessive genetic mutation in the MDR1 gene, which makes them sensitive to certain drugs, such as a common dewormer known as Ivermectin ... A genetic test for this recessive trait is available as well ...