Clonal studies define the proteic sequence of several allergens leading to the recombination and the use of them for immunotherapy extracts. It has been possible to clone the receptors for IgE in basophils and mast cells and the regulation mechanisms had been delucidates. In a near future it will be possible to design recombinant molecules for the specific inhibition of synthesis and receptors of IgE and avoid the signal transmissions and the release of mediators. The diagnosis of several diseases is based in molecular techniques, inclusive in uterus. Genes for various diseases had been cloned in immunology, recombinations with gamma interferon had been used for treatment of subjects with atopic dermatitis and chronic granulomatous disease.