Navigation Links
Trait


In biology, a trait or character is a genetically inherited feature of an organism. A synonym for trait is phenotype.

Contents

Definition of a trait

A trait may be any single feature or quantifiable measurement of an organism. However, the most useful traits for genetic analysis are present in different forms in different individuals.

A visible trait is the final product of many molecular and biochemical processes. In most cases, information starts with DNA traveling to RNA and finally to protein (ultimately affecting organism structure and function). This is the Central Dogma of molecular biology as stated by Francis Crick.

This information flow may also be followed through the Cell as it travels from the DNA in the Nucleus, to the Cytoplasm, to the Ribosomes and the Endoplasmic Reticulum, and finally to the Golgi Apparatus, which may package the final products for export outside the cell.

Cell products are released into the tissue, and organs of an organism, to finally affect the physiology in a way that produces a trait.

Environmental origin of traits

The environment plays a large role in the determination of traits. This is natural as all organisms must have input (and output) of energy and matter in order to maintain their overall elevated energy state.

Genetic origin of traits in diploid organisms

The heritable unit that may produce a trait is called a gene. A gene is a strand of DNA that is part of a very long and compacted string of DNA called a chromosome. An important reference point along this string is the centromere; the distance from a gene to the centromere is referred to as the gene's locus or map location. A chromosomal region known to control a trait while the responsible gene within not being identified is referred to as a quantitative trait locus.

The nucleus of a diploid cell contains two of each chromosome, with homologous (mostly identical) pairs of chromosomes having the same genes at the same loci.

Mendelian expression of genes in diploid organisms

A gene is only a DNA code sequence; the slightly different variations of that sequence are called alleles. Alleles can be significantly different and produce different product RNAs.

Combinations of different alleles thus go on to generate different traits through the information flow charted above. For example, if the alleles on homologous chromosomes exhibit a "simple dominance " relationship, the trait of the "dominant" allele shows in the phenotype.

Gregor Mendel pioneered modern genetics. His most famous analyses were based on clear-cut traits with simple dominance. He determined that the heritable units, he called "genes", occurred in pairs and could exhibit linkage. His tool was statistics: long before the molecular theory of DNA.

Biochemistry of dominance and extensions to expression of traits

The biochemistry of the intermediate proteins determines how they interact in the cell. Therefore, biochemistry predicts how combinations of different alleles will produce varying traits.

Extended expression patterns seen in diploid organisms include facets of incomplete dominance, codominance, and multiple alleles .

See also : genetics, skill

'"/>


(Date:4/5/2017)... SEATTLE , April 5, 2017  The Allen ... the Allen Cell Explorer: a one-of-a-kind portal and dynamic ... large-scale 3D imaging data, the first application of deep ... edited human stem cell lines and a growing suite ... the platform for these and future publicly available resources ...
(Date:4/3/2017)... WASHINGTON , April 3, 2017 /PRNewswire-USNewswire/ ... single-cell precision engineering platform, detected a statistically ... cell product prior to treatment and objective ... highlight the potential to predict whether cancer ... prior to treatment, as well as to ...
(Date:3/29/2017)... the health IT company that operates the largest health ... today announced a Series B investment from BlueCross BlueShield ... investment and acquisition accelerates higi,s strategy to create the ... activities through the collection and workflow integration of ambient ... secures data today on behalf of over 36 million ...
Breaking Biology News(10 mins):
Other biology definition