EXONS-INTRONS = LEXONS - IN-FRAME CONCATENATION OF EXONS BY PCR

A method for concatenating exons from genomic DNA, thereby skipping la rge stretches of intron sequence, has been developed using the polymer ase chain reaction (PCR) with primers based on known intron-exon junct ion sequences. The use of genomic DNA circumvents the need for cDNA pr eparation for many purposes, including cDNA construction and mutationa l analysis. This PCR method also facilitates the concatenation of nonc onsecutive exons, allowing different (known or hypothetical) splice fo rms to be amplified. We have used this technique to obtain concatamers of exons 3-9A of APC, a tumor suppressor gene that is mutated in spor adic colorectal cancers and in the germline of individuals with adenom atous polyposis coli. This method also facilitates the generation of a ny polymorphic derivative of a known sequence, even where the derivati ve differs from the available sequence at several positions. Hum Mutat 12:122-127, 1998. (C) 1998 Wiley-Liss, Inc.