**Group 1: Phenotype**
– Phenotype refers to observable characteristics or traits of an organism.
– It includes morphology, developmental processes, biochemical properties, behavior, and products of behavior.
– Phenotype results from genetic code expression (genotype) and environmental factors.
– Polymorphism occurs when multiple different phenotypes exist in a species.
– The concept of phenotype was distinguished from genotype by Wilhelm Johannsen in 1911.
**Group 2: Phenotypic Variation**
– Phenotypic variation is essential for evolution through natural selection.
– The genotype-environment-phenotype relationship influences the expression of traits.
– Genotypes can modify and express different phenotypes based on environmental conditions.
– Phenotypic variation can be observed in different habitats affecting the same species differently.
– Variation in traits can occur at levels below genes, impacting an organism’s fitness.
**Group 3: Behavioral Phenotypes**
– Behaviors and their consequences are considered phenotypes.
– Behavioral phenotypes include cognitive, personality, and behavioral patterns.
– Some behavioral phenotypes can characterize psychiatric disorders or syndromes.
– The study of behavioral phenotypes contributes to understanding complex traits.
– Behaviors are observable characteristics that contribute to an organism’s phenotype.
**Group 4: Phenome**
– The phenome refers to all traits expressed by an organism or its subsystems.
– It includes extragenic portions of cells, both cytoplasmic and nuclear.
– The phenome serves as the material basis of the phenotype, similar to how the genome relates to the genotype.
– Defining the phenome has been a challenge due to inconsistent usage and definitions.
– Researchers have proposed different definitions, including the phenome as a matrix of data representing an organism’s phenotypes.
**Group 5: Research and Applications**
– Phenome-wide association studies (PheWAS) use electronic health records linked to DNA biobanks to identify genotype-phenotype associations.
– Exploring relationships among phenotype, genotype, and environment at different levels aids in understanding complex traits.
– The concept of pan-phenome, pan-genome, and pan-envirome relationships was proposed in 2023.
– Plant biologists have started exploring the phenome in plant physiology studies.
– Understanding the interplay between genotype and phenotype is crucial for various fields, including medicine and evolutionary biology.
In genetics, the phenotype (from Ancient Greek φαίνω (phaínō) 'to appear, show', and τύπος (túpos) 'mark, type') is the set of observable characteristics or traits of an organism. The term covers the organism's morphology (physical form and structure), its developmental processes, its biochemical and physiological properties, its behavior, and the products of behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code (its genotype) and the influence of environmental factors. Both factors may interact, further affecting the phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and then again in his 1982 book The Extended Phenotype suggested that one can regard bird nests and other built structures such as caddisfly larva cases and beaver dams as "extended phenotypes".
Wilhelm Johannsen proposed the genotype–phenotype distinction in 1911 to make clear the difference between an organism's hereditary material and what that hereditary material produces. The distinction resembles that proposed by August Weismann (1834–1914), who distinguished between germ plasm (heredity) and somatic cells (the body). More recently, in The Selfish Gene (1976), Dawkins distinguished these concepts as replicators and vehicles.