Animal models and genetic effects

Question 1

What is an animal model?

Answer 1

A living, non-human being used to understand the biological basis of healthy and pathological human phenotypes.

Question 2

What are good criteria for an animal model?

Answer 2

Good face validity - the model resembles the human phenotype

Good construct validity - the model and the human phenotype share common biological underpinnings.

Good predictive validity - therapeutic drugs have the same effect in humans and the model. The model can be used to screen for new treatments.

Question 3

What are some advantages of using animal models?

Answer 3

Genomes are amenable to genetic manipulation

Experimental control - regulated genetic background

They are good breeders with short generation times

Can be maintained in large colonies

Have a wide repertoire of sophisticated behaviours

Access to neural tissue/ procedures that would not be ethical in humans

Question 4

What are some disadvantages of animal models?

Answer 4

Genetic/ physiological divergence from humans

Different evolutionary histories

Limited range of possible genetic modifications

Hard to look at age-related diseases as some human behaviours are complex and influenced by combined effect of many genes

Unable to accurately model some human phenotypes eg language, psychosis

Ethical issues with possible adverse effects

Models rarely have true face, construct and predictive validity

Question 5

What are some commonly used genetic animal models?

Answer 5

Nematode worm, Fruit fly, Rat, Zebrafish, Voles, Rhesus monkey and mouse sub-species