General information
The SALSA MLPA
Probemix P128 CYP450 is a
research use only (RUO) assay for the detection of deletions or duplications in the
GSTM1,
CYP1B1,
CYP3A4,
CYP3A5,
CYP2C19,
CYP2C9,
CYP2E1,
GSTP1,
CYP1A2,
CYP1A1,
CYP2A6,
CYP2B6,
GSTT1 and
CYP2D6 genes.
Cytochrome P450 enzymes are important in the biosynthesis and degradation of endogenous compounds such as steroids, lipids and vitamins. These enzymes reduce or alter the pharmacologic activity of many drugs and facilitate their elimination. Differences in drug metabolism in the intestine or liver between patients are major contributors to drug response, including adverse effects.
Glutathione transferases are a family of proteins that play an important role in detoxification by catalyzing the conjugation of many compounds with reduced glutathione.
In the normal population several of the targeted genes differ in copy number. More information per gene is given under Table 2.
The
GSTM1 gene (8 exons), spans ~5.9 kb of genomic DNA and is located on 1p13.3, 110 Mb from the p-telomere. The
CYP1B1 gene (3 exons), spans ~8.6 kb of genomic DNA and is located on 2p22.2, 38 Mb from p-telomere. The
CYP3A4 gene (13 exons), spans ~27 kb of genomic DNA and is located on 7q22.1, 99 Mb from the p-telomere. The
CYP3A5 gene (13 exons), spans ~32 kb of genomic DNA and is located on 7q22.1, 99 Mb from the p-telomere. The
CYP2C19 gene (9 exons), spans ~93 kb of genomic DNA and is located on 10q23.33, 97 Mb from the p-telomere. The
CYP2C9 gene (9 exons), spans ~51 kb of genomic DNA and is located on 10q23.33, 97 Mb from the p-telomere. The
CYP2E1 gene (9 exons), spans ~12 kb of genomic DNA and is located on 10q26.3, 135 Mb from the p-telomere (close to the q-telomere). The
GSTP1 gene (7 exons), spans ~2.8 kb of genomic DNA and is located on 11q13.2, 67 Mb from the p-telomere. The
CYP1A2 gene (7 exons), spans ~7.8 kb of genomic DNA and is located on 15q24.1, 73 Mb from the p-telomere. The
CYP1A1 gene (7 exons), spans ~6.0 kb of genomic DNA and is located on 15q24.1, 73 Mb from the p-telomere. The
CYP2A6 gene (9 exons), spans ~6.9 kb of genomic DNA and is located on 19q13.2, 46 Mb from the p-telomere. The
CYP2B6 gene (9 exons), spans ~27 kb of genomic DNA and is located on on 19q13.2, 46 Mb from the p-telomere. The
GSTT1 gene (5 exon), spans ~8.2 kb of genomic DNA and is located on 22q11.23, 23 Mb from the p-telomere. The
CYP2D6 gene (9 exons), spans ~4.3 kb of genomic DNA and is located on 22q13.2, 41 Mb from the p-telomere.
More information is available at
https://www.ncbi.nlm.nih.gov/books/NBK1419/.
Probemix content
The SALSA MLPA Probemix P128-D2 CYP450 contains 52 MLPA probes with amplification products between 128 and 504 nucleotides (nt). At least two probes are present for each of the targeted genes. In addition, 12 reference probes are included that detect autosomal chromosomal locations. Complete probe sequences and the identity of the genes detected by the reference probes are available online (
www.mrcholland.com).
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. More information on how to interpret observations on these control fragments can be found in the MLPA General Protocol and online at
www.mrcholland.com.