The invention relates to a method for producing carotenoids or their precursors using genetically modified organisms of the Blakeslea genus. Said method comprises the following steps (i) transformation of at least one of the cells, (ii) optional homokaryotic conversion of the cells obtained in step (i) to produce cells, in which one or more genetic characteristics of the nuclei are all modified in an identical manner and said modification manifests itself in the cells, (iii) selection and reproduction of the genetically modified cell or cells, (iv) cultivation of the genetically modified cells, (v) preparation of the carotenoids produced by the genetically modified cells or the carotenoid precursor produced by said genetically modified cells. The invention also relates to carotenoids or their precursors produced according to said method and to the use thereof.