Preventive and Predictive Genetics: A perspective
Advances in Predictive, Preventive and Personalised Medicine
Public Health practices focus on the implementation of programmes for health improvement and disease prevention (Khoury et al., Am J Prev Med 40(4):486-493, 2011). Public health initiatives in diseases were initially targeted to prevent infectious diseases. Partly due to the availability of vaccines and antimicrobial therapy and partly due to better standard of living, the world is free of diseases such as small pox, almost free of polio and the prevalence of infections such as malaria and HIV
... s steadily on the decline. This has meant that the human race is living longer with the result that non-communicable diseases have become a global public health priority. Preventing non-communicable diseases is a more logical approach than treating them, even more so when modifiable, common lifestyle risk factors share a role in the onset and progression of the disease. Preventive genetics plays a crucial role in the identification of subjects at risk at a very early age, which would thus give public health officials the necessary time to take appropriate action. Genetic tests can be classified into carrier, diagnostic and predictive testing. In carrier testing, the tests are directed towards the identification of carriers of autosomal recessive or X-linked genetic disorders to prevent disease. Preventive genetics can be defined as using genetics for the prevention of a future disease that has a genetic component either in the individual tested or in future offspring. Diagnostic testing is the process that identifies the current disease status of the subject and includes, among others, prenatal and newborn screening. The implementation of screening programmes allow the detection of genetic disorders at an early stage, so as to prevent these conditions or their serious consequences. Predictive testing 8 G. Grech et al. determines whether a subject with a positive history but no symptoms of the disease, is at risk of developing the disorder at a future date. In this chapter, we will discuss the application of genetic screening tests to monogenic disorders and complex disorders with monogenic subsets, in view of the current practices. The multifactorial aetiology of complex disorders involves multiple gene effects and gene-lifestyle interactions that cannot be singled out to give a strong predictive value. However, a subset of the complex disorders are caused by highly penetrant genetic mutations. Hence, in this chapter we shall also address predisposing syndromes with high predictive value. In addition, the need of biobanks will be discussed.