1. WHAT IS PHENOTYPING?
This means characterising the phenotype, that is, the functional expression of the genotype in a specific environment.
2. WHY IS PHENOTYPING IMPORTANT?
Phenotyping is an important part of studying animal models of human diseases generated by genetic modification, as it enables establishing the role of a specific gene in the structure and function of an organ or system and its implication in diseases with a genetic origin.
3. HOW IS PHENOTYPING DONE?
There are different levels of phenotyping, from molecular to functional, and many systems which have to be characterised when a new mutant is generated. Although there are databases and protocols available for carrying out these tests, the right technology, qualified personnel and the experience necessary to carry these out are needed, especially in secondary levels of analysis.
4. WHAT FACTORS MAY AFFECT PHENOTYPING?
A large number of factors affect phenotyping. Some of the “endogenous” factors to be stressed are the species, the strain and sex, as well as the age. Environmental factors, such as light, diet, temperature, noise, etc. are also important. All of these may alter the results of phenotyping tests and lead to wrong conclusions, which is why their effects must be taken into account and attempt to be minimised.
5. WHY IS A PHENOTYPING SERVICE LIKE SEFALer NECESSARY?
Rare diseases constitute a set of pathologies characterised by their low incidence, but which may affect different organs and systems, meaning that the symptoms are highly diverse and depend on the specific pathology. Analysing animal models of rare diseases requires a set of tests enabling quickly and simply evaluating the general phenotype, as well as more specific tests for detailed study of specific functions. The existence of a phenotyping service with different specialised units connected as a network facilitates comprehensive phenotyping.
6. WHAT ARE NON-INVASIVE TESTS?
These are the ones that preserve the animal’s life and reduce its stress and discomfort as far as possible. They are optimal from the bioethical standpoints as they contribute to Russell and Burch 3Rs maxim (Replacement, Reduction, Refinement). They also enable performing repeated evaluations on the same individual, essential in longitudinal studies (ageing, degeneration/regeneration, pharmaceutical and toxicological tests, etc.).