Talking Glossary of Genetic Terms
A trait is a specific characteristic of an organism. Traits can be determined by genes or the environment, or more commonly by interactions between them. The genetic contribution to a trait is called the genotype. The outward expression of the genotype is called the phenotype.
Trait is a specific characteristic of an individual. For example, their hair color or their blood type. Traits are determined by genes, and also they are determined by the interaction with the environment with genes. And remember that genes are the messages in our DNA that define individual characteristics. So the trait is the manifestation of the product of a gene that is coded for by the DNA. The word "phenotype" is sometimes used interchangeably with the word trait, and "phenotype" may also define a whole compendium of traits together.
Name: Donna Krasnewich, M.D., Ph.D.
Occupation: Former Deputy Clinical Director, Office of the Clinical Director; Former Staff Clinician, Medical Genetics Branch
Biography: Dr. Krasnewich's research has investigated metabolically and biochemically based developmental delay disorders, especially those involving defects in sugar metabolism. Sugars are important for brain development and the proper functioning of other organs in the body. A group of genetic defects in sugar metabolism are termed congenital disorders of glycosylation (CDG), which result from abnormal carbohydrate metabolism, specifically the abnormal synthesis of N-linked oligosaccharides. About 400 cases of CDG are known worldwide, although given the variable clinical presentations of CDG, many individuals likely go undiagnosed.