General information
SALSA
® MLPA
® Probemix P242 Pancreatitis is a
research use only (RUO) assay for the detection of deletions, duplications or genomic rearrangements in the
CTRC,
SPINK1,
PRSS1 and
PRSS2 genes, which are associated with hereditary pancreatitis. This probemix includes probes for the
TRD-AS1 gene as an aid to interpret
PRSS1 and
PRSS2 copy numbers when larger regions are affected (see Appendix 1). This probemix also detects the presence of the
SPINK1 p.N34S (c.101A>G),
PRSS1 p.N29I (c.86A>T) and
PRSS1 p.R122H (c.365G>A) point mutations.
Hereditary Pancreatitis (HP; OMIM # 167800) is characterised by recurrent episodes of inflammation of the pancreas that progress to chronic pancreatitis. HP has an autosomal dominant pattern of inheritance and is defined by two or more individuals with pancreatitis in two or more generations of a family, or pancreatitis associated with a known germline pathogenic variant.
PRSS1 encodes trypsin-1 (cationic trypsinogen), a major pancreatic digestive serine peptidase enzyme, which is produced and secreted by the pancreas.
PRSS1 pathogenic variants typically result in a trypsin protein that is either prematurely activated, while it is still in the pancreas, or resistant to degradation. Duplication of
PRSS1, leading to an increase of the protein, also causes HP. Duplication and triplication of a ~605-kb segment containing
PRSS1 and
PRSS2 have been described (Chauvin et al. 2009). Furthermore, gene conversion between
PRSS1 and
PRSS2 has been reported (Nemeth and Sahin-Tóth 2014, Rygiel et al. 2015). In 90% of the cases, hereditary pancreatitis is caused by two point mutations in the
PRSS1 gene, R122H (~65%) and N29I (~25%) (Nemeth and Sahin-Tóth 2014). Gene conversion between
PRSS1 and
PRSS2 exon 2 and intron 2 can occur, resulting in the N29I mutation together with N54S, a non-pathogenic mutation (Teich et al. 2005). Masson et al. (2008a) identified a hybrid
PRSS1/
PRSS2 duplication in which exons 1 and 2 were derived from
PRSS2 and exons 3 to 5 from
PRSS1, which also contained the
PRSS1 N29I mutation. In less than 6% of the cases, HP is caused by
PRSS1 (large) deletions/duplications.
SPINK1 encodes the serine protease inhibitor Kazal-type 1. Pathogenic variants in
SPINK1 are associated with increased risk of pancreatitis and have been identified in approximately 20% of families with hereditary pancreatitis, without a
PRSS1 germline pathogenic variant. The risk for developing acute pancreatitis is highly increased when the N34S mutation in
SPINK1 is present (Koziel et al. 2015).
CTRC encodes chymotrypsin C (CTRC), a low-abundance pancreatic digestive enzyme that is synthetized with PRSS1. CTRC is important for the degradation of the prematurely activated trypsin within the pancreas. Pathogenic variants of
CTRC have been associated with chronic pancreatitis (Masson et al. 2008b).
While identification of a heterozygous
PRSS1 pathogenic variant confirms a diagnosis of hereditary pancreatitis, the presence of isolated pathogenic variants in the
SPINK1 or
CTRC genes is insufficient to cause pancreatitis (Masson et al. 2013).
The
CTRC gene (8 exons) spans ~11 kb of genomic DNA and is located on 1p36.21, about 15 Mb from the p-telomere. The
SPINK1 gene (4 exons) spans ~7.1 kb of genomic DNA and is located on 5q32, about 148 Mb from the p-telomere. The
PRSS1 gene (5 exons) spans ~3.6 kb of genomic DNA and is located on 7q34, about 143 Mb from the p-telomere. The
PRSS2 gene (5 exons) spans ~3.6 kb of genomic DNA and is located on 7q34, about 143 Mb from the p-telomere. The
TRD-AS1 gene (5 exons) spans ~104 kb of genomic DNA and is located on 14q11.2, about 22 Mb from the p-telomere.
More information is available at
https://www.ncbi.nlm.nih.gov/books/NBK190101 and
https://www.ncbi.nlm.nih.gov/books/NBK84399 .
This product is not CE/FDA registered for use in diagnostic procedures. The SALSA® MLPA® technique is covered by US patent 6,955,901 and corresponding patents outside the US. The purchase of this product includes a license to use only this amount of product solely for the purchaser’s own use.
Probemix content
P242-D1 Pancreatitis contains 41 MLPA probes with amplification products between 124 and 409 nucleotides (nt). This includes eight probes for the
CTRC gene, six probes for the
SPINK1 gene (one of which is a flanking probe), nine probes for the
PRSS1 gene (one of which is a flanking probe), five probes for the
PRSS2 gene (three of which are flanking probes) and three probes for the
TRD-AS1 gene. These include three probes specific for the
SPINK1 p.N34S (c.101A>G),
PRSS1 p.N29I (c.86A>T) and
PRSS1 p.R122H (c.365G>A) mutations which will only generate a signal when the mutation is present. In addition, ten 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 .
Sample DNA
Sample DNA developed for this product:
The product description of this Sample DNA can be found on this page under
Online available downloads >
Other product documentation.