[Clinical validity and clinical utility of molecular-genetic laboratory testing]

Intensity of genetic determination of our phenotypes differs both quantitatively and qualitatively and concerns not only physiological, but also pathological features. Clinical diagnoses are more and more dependent on laboratory findings, whose quality and utility have to be objectively estimated and assesed. For medical practice the knowledge of genetic determination is substantial and for this reason several approaches have beeen adopted. Genetic determination can be measured and expressed by several parameters, of which heritability and genetic risk are discussed in this paper to elucidate their properties, importace, significance, and limitations.