MOLECULAR-GENETICS OF THYROID-DISEASES

Over the past 20 years, recombinant deoxyribonucleic acid technology h as led to the cloning of three major thyroid specific protein genes (t hyroglobulin, thyroperoxidase and thyrotrophin receptor), which happen to be also the main thyroid autoantigens implicated in thyroid diseas es. In this context, the impact that molecular genetics has had on the understanding of aetiopathogeny and diagnosis of thyroid diseases is summarized, with special emphasis on a recently discovered genetic mec hanism responsible for toxic nodules. One fruitful outcome of the basi c research on thyroid-specific gene expression has been the possibilit y of targeting the expression of a series of genes to the thyroid in t ransgenic mice. The result is the availability of mouse models mimicki ng human thyroid diseases such as destructive hypothyroidism, hyperact ive thyroid adenomas and thyroid cancers exhibiting varying levels of differentiation.