NM_000249.4:c.546-9C>T

Variant names:

• chr3-37011811-C-T
• rs878853789
• NM_000249.4:c.546-9C>T

Variant summary

Our verdict is Benign. The variant received -10 ACMG points: 2P and 12B. PM2 BP4_Strong BP6_Very_Strong

The NM_000249.4(MLH1):​c.546-9C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,612,028 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MLH1 NM_000249.4 intron
• Scores: Splicing: ADA: 0.1114
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:4
• Conservation: PhyloP100: 0.500
• Publications: 0 publications found

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]

MLH1 Gene-Disease associations (from GenCC):

• Lynch syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, ClinGen, Orphanet
• Lynch syndrome 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Genomics England PanelApp
• Muir-Torre syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Genomics England PanelApp, Ambry Genetics, G2P, Orphanet
• mismatch repair cancer syndrome 1

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), Orphanet, ClinGen
• Lynch syndrome 1

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• ovarian cancer

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• malignant pancreatic neoplasm

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• rhabdomyosarcoma

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
• prostate cancer

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• breast cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics
• hereditary breast carcinoma

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Benign. The variant received -10 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.54).
• BP6: Variant 3-37011811-C-T is Benign according to our data. Variant chr3-37011811-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 455444.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000249.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MLH1	NM_000249.4	MANE Select	c.546-9C>T		intron	N/A	NP_000240.1
	MLH1	NM_001354628.2		c.546-9C>T		intron	N/A	NP_001341557.1
	MLH1	NM_001354629.2		c.447-9C>T		intron	N/A	NP_001341558.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MLH1	ENST00000231790.8	TSL:1 MANE Select	c.546-9C>T		intron	N/A	ENSP00000231790.3
	MLH1	ENST00000456676.7	TSL:1	c.546-9C>T		intron	N/A	ENSP00000416687.3
	MLH1	ENST00000413740.2	TSL:1	c.546-9C>T		intron	N/A	ENSP00000416476.2

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 151932 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460096 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 726486

African (AFR) AF: 0.00 AC: 0 AN: 33434

American (AMR) AF: 0.00 AC: 0 AN: 44692

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26112

East Asian (EAS) AF: 0.00 AC: 0 AN: 39670

South Asian (SAS) AF: 0.00 AC: 0 AN: 86178

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53394

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1110520

Other (OTH) AF: 0.0000166 AC: 1 AN: 60334

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 151932 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74196

African (AFR) AF: 0.00 AC: 0 AN: 41366

American (AMR) AF: 0.00 AC: 0 AN: 15250

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.000193 AC: 1 AN: 5190

South Asian (SAS) AF: 0.00 AC: 0 AN: 4820

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10560

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 67962

Other (OTH) AF: 0.00 AC: 0 AN: 2086

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Likely benign

Submissions summary: Benign:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Colorectal cancer, hereditary nonpolyposis, type 2 Benign:1

Nov 19, 2024

Myriad Genetics, Inc.

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely benign. This variant is intronic and is not expected to impact mRNA splicing.

not provided Benign:1

Apr 22, 2019

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at a significant frequency in large population cohorts (Lek et al., 2016)

Hereditary nonpolyposis colorectal neoplasms Benign:1

Feb 02, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Hereditary cancer-predisposing syndrome Benign:1

Jun 26, 2019

Color Diagnostics, LLC DBA Color Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.54
CADD	Benign	17
DANN	Benign	0.83
PhyloP100		0.50

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.11
dbscSNV1_RF	Benign	0.47
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs878853789; hg19: chr3-37053302;