Identification of genomic deletions of the APC gene in familial adenomatous polyposis by two independent quantitative techniques.

• Large deletions in the APC (adenomatous polyposis coli) gene, causing familial adenomatous polyposis (FAP), cannot easily be detected by conventional mutation-detection techniques. Therefore, we have developed two independent quantitative methods for the detection of large deletions, encompassing one or more exons, of APC. Multiplex ligation-dependent probe amplification (MLPA) is performed in one reaction for the initial quantification of all APC exon copy numbers. Subsequently, quantitative real-time PCR (QRT-PCR) is used to verify the results obtained in the MLPA reaction. The identification of a deletion of the whole APC gene in a patient with classical FAP is described. The mutation was detected with the two quantitative methods and further verified on chromosomal level by the use of FISH (fluorescence in situ hybridization) on metaphase spreads. Furthermore, a large deletion covering exons 11-13 of the APC gene was detected in two apparently unrelated families. This deletion was further verified and characterized with long-range PCR. The MLPA test ensures a sensitive high-throughput screening for large deletions of the APC gene and can easily be implemented in the diagnostic testing for FAP.

Nyckelord

Adenomatous Polyposis Coli

diagnosis

genetics

Adenomatous Polyposis Coli Protein

genetics

Adult

DNA Mutational Analysis

methods

Exons

genetics

Female

Gene Deletion

Gene Dosage

Genes

APC

Humans

In Situ Hybridization

Fluorescence

Karyotyping

Male

Middle Aged

Polymerase Chain Reaction

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)