HUMAN DISEASE AND DRUG THERAPY

Human disease

The wide range of diseases to which humans are exposed have in common the fact that each is the result of either some physiological dysfunction caused by a gene mutation or incorrect expression of the related protein, or of the exposure of the individual to an environmental factor, such as pesticides, diet, or bacterial, fungal or viral infection. The dysfunction gives rise to characteristic medical symptoms that enable the condition to be diagnosed, commonly by diagnostic tests of the type described in Chapter 16, and an evaluation made of the severity of the condition and the future prospects of the patient making a full recovery from it. Underlying many of the conditions at a molecular level is a change in the amount, function or activity of one or more proteins that in turn trigger changes in cellular, tissue or organ function. A large part of current worldwide medical research is aimed at the elucidation of the molecular mechanisms underlying diseases such as the various forms of cancer and neurological conditions such as Parkinson's disease, motor neurone disease and multiple sclerosis, in order to identify key proteins involved in the disease process with a view to selecting one of the proteins as a target for the development of a new drug and thereby to minimise or eliminate the symptoms.