1. Identification of a deletion in the mismatch repair gene, MSH2, using mouse-human cell hybrids monosomal for chromosome 2
- Author
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R E, Pyatt, H, Nakagawa, H, Hampel, M, Sedra, M B, Fuchik, I, Comeras, A, de la Chapelle, and T W, Prior
- Subjects
Male ,DNA Repair ,Base Pair Mismatch ,Exons ,Sequence Analysis, DNA ,Hybrid Cells ,Colorectal Neoplasms, Hereditary Nonpolyposis ,Pedigree ,Blotting, Southern ,Mice ,Chromosomes, Human, Pair 2 ,Animals ,Autoradiography ,Humans ,Female ,Gene Deletion ,Ohio - Abstract
Hereditary non-polyposis colorectal cancer is characterized by mutations in one of the DNA mismatch repair genes, primarily MLH1, MSH2, or MSH6. We report here the identification of a genomic deletion of approximately 11.4 kb encompassing the first two exons of the MSH2 gene in two generations of an Ohio family. By Southern blot analysis, using a cDNA probe spanning the first seven exons of MSH2, an alteration in each of three different enzyme digests (including a unique 13-kb band on HindIII digests) was observed, which suggested the presence of a large alteration in the 5' region of this gene. Mouse-human cell hybrids from a mutation carrier were then generated which contained a single copy each of human chromosome 2 on which the MSH2 gene resides. Southern blots on DNA from the cell hybrids demonstrated the same, unique 13-kb band from one MSH2 allele, as seen in the diploid DNA. DNA from this same monosomal cell hybrid failed to amplify in polymerase chain reactions (PCRs) using primers to exons 1 and 2, demonstrating the deletion of these sequences in one MSH2 allele, and the breakpoints involving Alu repeats were identified by PCR amplification and sequence analysis.
- Published
- 2003