The SALSA MLPA probemix P087 BRCA1 Confirmation is an in vitro diagnostic (IVD)1
or a research use only (RUO) assay for the confirmation of deletions or duplications in the human BRCA1 gene as initially observed using the SALSA MLPA probemix P002 BRCA12
. This assay is for use with human genomic DNA extracted from peripheral blood and not for use with DNA extracted from formalin-fixed paraffin embedded or fresh tumour materials. The probemix is not intended to be used as a standalone assay for clinical decisions. The results of this test should be interpreted by a clinical molecular geneticist or equivalent.
Please note that this probemix is for In Vitro Diagnostic use (IVD) in the countries specified at the end of this product description. In all other countries, the product is for Research Use Only (RUO).
The P002 BRCA1 probemix should be used as first tier probemix, because its coverage of the BRCA1 gene is more extensive.
Germline defects in the BRCA1 gene are the most frequent cause of a hereditary predisposition to breast cancer. Features characteristic of hereditary, versus sporadic, breast cancer are: younger age at diagnosis, frequent bilateral disease, and more frequent occurrence of disease among male relatives. Mutations in the BRCA1 and BRCA2 genes account for about 20 to 25% of hereditary breast cancers and about 5 to 10% of all breast cancers. In addition, mutations in the BRCA1 and BRCA2 genes account for around 15% of ovarian cancers overall.
More information is available at http://www.ncbi.nlm.nih.gov/books/NBK1247/
The great majority of germline defects in the BRCA1 gene are point mutations that can be detected by sequence analysis. Deletions and duplications of complete exons in the BRCA1 gene are the second most common cause of defects in the BRCA1 gene. These copy number changes are usually missed by amplicon-based sequencing analysis (Sanger sequencing or Next Generation Sequencing), but can be detected by the MLPA technique and hence MLPA complements sequence analysis of the BRCA1 gene. Large genomic rearrangements in BRCA1 may account for up to one-third of all disease-causing mutations, dependent on the population (Hansen et al. 2009). For example in Italian hereditary breast and ovarian cancer (HBOC) families the prevalence is 23% (Montagna et al. 2003), in the Netherlands 27%-36% (Hogervorst et al. 2003; Petrij-Bosch et al. 1997), while in a Danish cohort of HBOC patients the prevalence was 3.8% (Thomassen et al. 2006).
This SALSA MLPA probemix P087 BRCA1 Confirmation contains 40 MLPA probes with amplification products between 130 nt and 463 nt (Table 1), including 28 probes for the BRCA1 region (Table 2) and 12 reference probes that detect sequences outside this region. The identity of the genes detected by the reference probes is available online (www.mlpa.com
At least one MLPA probe is present for each exon in the major BRCA1 transcript variant 1. Three probes are present for exon 11 and two probes for exon 1a and exon 13. To determine the extent of a deletion/duplication, one probe is present in the upstream region of BRCA1 (0.9 kb before exon 1a).
This Probemix contains nine quality control fragments generating amplification products between 64 and 105 nt: four DNA Quantity Fragments (Q-fragments), two DNA Denaturation Fragments (D-fragments), one benchmark fragment, and one chromosome X and one chromosome Y-specific fragment (see table in the product description). More information on how to interpret observations on these control fragments can be found in the MLPA General Protocol and online at www.mlpa.com
SALSA Artificial Duplication DNA SD024:
In case no positive DNA sample is available in your laboratory, an artificial duplication DNA sample for this probemix (catalogue number SD024) can be ordered from MRC-Holland. This SD024 Artificial Duplication DNA will show a duplication of two or three probes when using the following probemixes: P002 and P087 BRCA1; P045, P090 and P077 BRCA2. The SD024 Artificial Duplication DNA is a mixture of human female genomic DNA and a titrated amount of plasmid containing selected probe target sequences. For further details, please consult the SD024 Artificial Duplication DNA product description, available online: www.mlpa.com. This product is for research use only (RUO).
Sample DNA developed for this product: