Cloning microdissection

Fig. 2. Methods for production of identical catde. (a) Embryo spHtting. A microdissection knife is used to cut an early embryo into two identical halves, (b) Embryo cloning. A cell from a morula stage embryo is removed and then inserted into an oocyte that has had its nucleus removed. EoUowing fusion of the two cells the newly produced one-ceU embryo is identical to the original morula. The procedure can be repeated to give multiple copies of the original...

Another use of polytene chromosomes is microdissection of DNA for cloning (Fig. 26-14). A piece of DNA containing 100-400 kb can be cut out of any desired spot, cleaved with restriction enzymes, and cloned.282 Since it has been estimated that Drosophila may contain only -9000-17,000 genes there may be 2-3 genes per band in these chromosomes.283 The technique has been extended to human and other mammalian chromosomes.284... 

Ray, M., Guan, X., Slovak, M Trent, J., and Meltzer, P. (1994) Rapid detection, cloning and molecular cytogenetic characterization of sequences from an MRP-encoding amplicon by chromosome microdissection. Br. J. Cancer 70, 85-90. 

This chapter illustrates the characterizations of technical procedures necessary in the course of these molecular evaluations, describing our laboratory experience and suggesting different diagnostic approaches microdissection techniques, extraction of nucleic acids from paraffin-embedded tissues, polymerase chain reaction (PCR), direct sequencing, and allelic separation by cloning [4-7],... 

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