One of the major research challenges in both the biologicaland biomedical sciences is reproducibility in the pathology of cancers andneurological disorders. Invasive molecular analyses often can reveal importantfactors that lead to a disease state if that certain disorder has a geneticbasis. However, these tests can very rarely be done on humans, so it is commonto use an analogous model organism, usually rat or mouse. Yet, this relies onthe idea that these model organisms can reliably reflect the true disease stateof humans.
In recent years, this has shown to be a problem in research oncertain cancers and neurological disorders such as Alzheimer’s. In each case, but for different reasons, therat and mouse models have been unreliable in reproducing the same disease statewith the same genetic manipulation. For cancer, environmental factors and the exploitationof specific oncogenes can have a drastic effect on the pathology of a certaincancer. With the advent of new studies that may not be reproducible,pharmaceutical companies may invest in methods that will have little to noeffect in patients with a certain form of cancer.
This has been one of the mainreasons for the push for genomic screening and personalized medicine. ForAlzheimer’s, the reigning hypothesis has involved the presence of Tau tanglesand beta-amyloid plaques that interrupt axonal communication leading toapoptosis. Although this seems to be a relatively consistent pathological statein humans, the results are extremely variable when testing in rats and mice. Oftentimes,the animal models do not reflect the neuronal and synaptic loss that ischaracteristic of the pathological state in Alzheimer’s disease. Untilresearchers in these respective fields are able to successfully reproduce thephysiological characteristics of these highly variable disorders in basicresearch, it will be impossible to translate experimental drugs to humans.