Trait (genetics)

Trait refers to observable characteristics of an organism. Traits arise from the mere expression of geness, or from gene expression and the effects of the external environment. The set of all traits of an organism is called the phenotype. According to the nature of the traits, we distinguish:
 * Quantitative traits (measurable): male and female height, growth parameters, weight, blood pressure, IQ. A specific category of quantitative traits are meristic traits, described by counting integers (number of fingers, number of pups in a litter, etc.).
 * Qualitative traits (not measurable): morphological developmental defects, eye colour, psyche, talent.

Related articles

 * Genes
 * Genotype
 * Phenotype
 * Mendel's experiments