Abstract: Detection of mutations in a lacZ gene including lacZ operator sequence functioning as marker gene located in a plasmid whereof one or more copies are introduced into the DNA of a mammal or of a mammalian cell, by isolating the DNA, cutting the plasmid out of the DNA, picking up the plasmid DNA with solid particles to which a lacZ operator binding material is bound, again releasing the plasmid from the solid particles after isolation and subsequently circularizing the plasmid, transforming a host restriction-negative, lacZ-negative and galE-negative bacterial host with the plasmid and separating transformants with mutated lacZ gene which grow on a lactose-containing medium from transformants with a non-mutated lacZ gene which do not grow on such a medium. A transgenic mammal model for mutation analysis.

Abstract: The invention relates to an apparatus for two-dimensional electrophoresis of at least one electrophoresis unit comprising an electrophoresis medium enclosed between two plates, which apparatus comprises a first pair and a second pair of compartments for electrophoresis liquid which are provided with electrodes and which make electrophoretic contact on either side and mutually transversely of each other with the electrophoresis medium of the electrophoresis unit, wherein the compartments are disposed and adapted such that the electrophoresis unit assumes a standing position in the apparatus, and to an electrophoresis unit intended for such an apparatus.