rs267607852
Variant summary
Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1_ModeratePM2PP5_Very_Strong
The NM_000249.4(MLH1):c.1732-2A>C variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).
Frequency
Genomes: not found (cov: 31)
Consequence
MLH1
NM_000249.4 splice_acceptor, intron
NM_000249.4 splice_acceptor, intron
Scores
5
1
1
Splicing: ADA: 1.000
2
Clinical Significance
Conservation
PhyloP100: 7.25
Genes affected
MLH1 (HGNC:7127): (mutL homolog 1) The protein encoded by this gene can heterodimerize with mismatch repair endonuclease PMS2 to form MutL alpha, part of the DNA mismatch repair system. When MutL alpha is bound by MutS beta and some accessory proteins, the PMS2 subunit of MutL alpha introduces a single-strand break near DNA mismatches, providing an entry point for exonuclease degradation. The encoded protein is also involved in DNA damage signaling and can heterodimerize with DNA mismatch repair protein MLH3 to form MutL gamma, which is involved in meiosis. This gene was identified as a locus frequently mutated in hereditary nonpolyposis colon cancer (HNPCC). [provided by RefSeq, Aug 2017]
Genome browser will be placed here
ACMG classification
Classification made for transcript
Verdict is Pathogenic. Variant got 12 ACMG points.
PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.07221489 fraction of the gene. Cryptic splice site detected, with MaxEntScore 3.2, offset of -31, new splice context is: atttggatgctccgttaaAGctt. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 3-37047517-A-C is Pathogenic according to our data. Variant chr3-37047517-A-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 455400.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
MLH1 | NM_000249.4 | c.1732-2A>C | splice_acceptor_variant, intron_variant | ENST00000231790.8 | NP_000240.1 |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
MLH1 | ENST00000231790.8 | c.1732-2A>C | splice_acceptor_variant, intron_variant | 1 | NM_000249.4 | ENSP00000231790.3 |
Frequencies
GnomAD3 genomes Cov.: 31
GnomAD3 genomes
Cov.:
31
GnomAD4 exome Cov.: 31
GnomAD4 exome
Cov.:
31
GnomAD4 genome Cov.: 31
GnomAD4 genome
Cov.:
31
ClinVar
Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link
Submissions by phenotype
Lynch syndrome 1 Pathogenic:1
Pathogenic, criteria provided, single submitter | clinical testing | University of Science and Technology Houari Boumediene, Laboratory of Molecular and Cellular Biology (LBCM) | - | - - |
not provided Pathogenic:1
Likely pathogenic, criteria provided, single submitter | clinical testing | Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital | Aug 15, 2023 | - - |
Hereditary nonpolyposis colorectal neoplasms Pathogenic:1
Pathogenic, criteria provided, single submitter | clinical testing | Labcorp Genetics (formerly Invitae), Labcorp | Jan 24, 2024 | This sequence change affects an acceptor splice site in intron 15 of the MLH1 gene. RNA analysis indicates that disruption of this splice site induces altered splicing and likely results in a shortened protein product. This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with Lynch syndrome (PMID: 8571956, 24090359; Invitae). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 455400). Studies have shown that disruption of this splice site results in skipping of 16, but is expected to preserve the integrity of the reading-frame (PMID: 24090359). This variant disrupts the p.Ala619 amino acid residue in MLH1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 10612827, 18561205, 21404117, 21520333, 28514183). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. - |
Hereditary cancer-predisposing syndrome Pathogenic:1
Pathogenic, criteria provided, single submitter | clinical testing | Ambry Genetics | Aug 11, 2016 | The c.1732-2A>C intronic pathogenic mutation results from an A to C substitution two nucleotides upstream from coding exon 16 in the MLH1 gene. This nucleotide position is highly conserved in available vertebrate species. Using the BDGP and ESEfinder splice site prediction tools, this alteration is predicted to abolish the native splice acceptor site; however, direct evidence is unavailable. Alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. As such, this alteration is classified as pathogenic. - |
Computational scores
Source:
Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
D
BayesDel_noAF
Pathogenic
CADD
Pathogenic
DANN
Uncertain
Eigen
Pathogenic
Eigen_PC
Pathogenic
FATHMM_MKL
Pathogenic
D
GERP RS
RBP_binding_hub_radar
RBP_regulation_power_radar
Splicing
Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
dbscSNV1_RF
Pathogenic
SpliceAI score (max)
Details are displayed if max score is > 0.2
DS_AG_spliceai
Position offset: 42
DS_AL_spliceai
Position offset: 2
Find out detailed SpliceAI scores and Pangolin per-transcript scores at