Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate
The NM_000249.4(MLH1):c.1243G>A(p.Asp415Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000991 in 1,613,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).
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]
Uncertain significance, criteria provided, single submitter
clinical testing
Color Diagnostics, LLC DBA Color Health
Mar 13, 2019
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Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Apr 19, 2023
The p.D415N variant (also known as c.1243G>A), located in coding exon 12 of the MLH1 gene, results from a G to A substitution at nucleotide position 1243. The aspartic acid at codon 415 is replaced by asparagine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Colorectal cancer, hereditary nonpolyposis, type 2 Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Baylor Genetics
Aug 09, 2023
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Breast and/or ovarian cancer Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Aug 27, 2021
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Muir-Torré syndrome;C1333991:Colorectal cancer, hereditary nonpolyposis, type 2;C5399763:Mismatch repair cancer syndrome 1 Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
Fulgent Genetics, Fulgent Genetics
May 23, 2017
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Lynch syndrome Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
All of Us Research Program, National Institutes of Health
Jul 20, 2024
This missense variant replaces aspartic acid with asparagine at codon 415 of the MLH1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with breast cancer (PMID: 25186627). This variant has been identified in 4/251316 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitter
clinical testing
GeneDx
Jun 17, 2021
Not observed at significant frequency in large population cohorts (Lek 2016) In silico analysis supports that this missense variant does not alter protein structure/function Observed in individuals with breast cancer (Tung 2015) This variant is associated with the following publications: (PMID: 22753075, 27535533, 25186627) -
Uncertain significance, criteria provided, single submitter
clinical testing
Labcorp Genetics (formerly Invitae), Labcorp
Jan 20, 2024
This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 415 of the MLH1 protein (p.Asp415Asn). This variant is present in population databases (rs373767220, gnomAD 0.004%). This variant has not been reported in the literature in individuals affected with MLH1-related conditions. ClinVar contains an entry for this variant (Variation ID: 182524). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt MLH1 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -