3-37008804-T-G

Variant names:

• chr3-37008804-T-G
• rs1260098414
• NM_000249.4:c.454-10T>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM2 PP3 BP6

The NM_000249.4(MLH1):​c.454-10T>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,455,942 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 Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MLH1 NM_000249.4 intron
• Scores: Splicing: ADA: 0.9994
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:2
• Conservation: PhyloP100: 2.32
• 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: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.
• BP6: Variant 3-37008804-T-G is Benign according to our data. Variant chr3-37008804-T-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 439179.We mark this variant Likely_benign, oryginal submission is: [Conflicting_classifications_of_pathogenicity].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MLH1	NM_000249.4	c.454-10T>G		intron_variant	Intron 5 of 18	ENST00000231790.8	NP_000240.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MLH1	ENST00000231790.8	c.454-10T>G		intron_variant	Intron 5 of 18	1	NM_000249.4	ENSP00000231790.3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD2 exomes AF: 0.00000796 AC: 2 AN: 251128 AF XY: 0.00000737

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1455942 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 724720

African (AFR) AF: 0.00 AC: 0 AN: 33338

American (AMR) AF: 0.0000447 AC: 2 AN: 44714

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26100

East Asian (EAS) AF: 0.00 AC: 0 AN: 39654

South Asian (SAS) AF: 0.00 AC: 0 AN: 86138

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

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5756

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1106670

Other (OTH) AF: 0.00 AC: 0 AN: 60178

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Lynch syndrome Uncertain:1

Sep 17, 2023

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant causes a T to G nucleotide substitution at the -10 position of intron 5/18 of the MLH1 gene. Splice site prediction tools predict that this variant may have an impact on RNA splicing. To our knowledge, RNA studies have not been reported for this variant. This variant has not been reported in individuals affected with MLH1-related disorders in the literature. This variant has been identified in 2/251128 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

Dec 16, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); Has not been previously published as pathogenic or benign to our knowledge; In silico analysis is inconclusive as to whether the variant alters gene splicing. In the absence of RNA/functional studies, the actual effect of this sequence change is unknown. -

not specified Benign:1

Sep 30, 2024

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary nonpolyposis colorectal neoplasms Benign:1

May 06, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.53
CADD	Benign	15
DANN	Benign	0.82
PhyloP100		2.3

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.82
SpliceAI score (max)		0.34		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.34		Position offset: 10

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

Other links and lift over

dbSNP: rs1260098414; hg19: chr3-37050295;