rs267607718

Variant names:

• chr3-36996710-G-A
• rs267607718
• NM_000249.4:c.207+1G>A

Your query was ambiguous. Multiple possible variants found:

• chr3-36996710-G-A
• chr3-36996710-G-C
• chr3-36996710-G-T

Variant summary

Our verdict is Pathogenic. The variant received 22 ACMG points: 22P and 0B. PVS1 PS3 PM2 PP5_Very_Strong

The NM_000249.4(MLH1):​c.207+1G>A variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,609,672 control chromosomes in the GnomAD database, with no homozygous occurrence. 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 (★★★). ClinVar reports functional evidence for this variant: "SCV000172723: RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data).".

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MLH1 NM_000249.4 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic reviewed by expert panel P:10
• Conservation: PhyloP100: 9.51
• Publications: 6 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: ClinGen, Orphanet, G2P
• 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: Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics, G2P, 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: Pathogenic. The variant received 22 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PS3: PS3 evidence extracted from ClinVar submissions: SCV000172723: RNA studies have demonstrated that this alteration results in abnormal splicing in the set of samples tested (Ambry internal data).
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 3-36996710-G-A is Pathogenic according to our data. Variant chr3-36996710-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 90020.Status of the report is reviewed_by_expert_panel, 3 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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MLH1	NM_000249.4	MANE Select	c.207+1G>A		splice_donor intron	N/A	NP_000240.1	P40692-1
	MLH1	NM_001354628.2		c.207+1G>A		splice_donor intron	N/A	NP_001341557.1	A0A087WX20
	MLH1	NM_001354629.2		c.207+1G>A		splice_donor intron	N/A	NP_001341558.1	A0AAQ5BGZ2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MLH1	ENST00000231790.8	TSL:1 MANE Select	c.207+1G>A		splice_donor intron	N/A	ENSP00000231790.3	P40692-1
	MLH1	ENST00000456676.7	TSL:1	c.207+1G>A		splice_donor intron	N/A	ENSP00000416687.3	H0Y818
	MLH1	ENST00000413740.2	TSL:1	c.207+1G>A		splice_donor intron	N/A	ENSP00000416476.2	H0Y806

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152198 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000483

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

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: 0.00000137 AC: 2 AN: 1457474 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 725496

African (AFR) AF: 0.0000300 AC: 1 AN: 33388

American (AMR) AF: 0.00 AC: 0 AN: 44710

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26118

East Asian (EAS) AF: 0.00 AC: 0 AN: 39658

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86158

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53396

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1108044

Other (OTH) AF: 0.00 AC: 0 AN: 60244

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152198 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74352

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000483 AC: 2 AN: 41444

American (AMR) AF: 0.00 AC: 0 AN: 15284

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5200

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10614

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68034

Other (OTH) AF: 0.00 AC: 0 AN: 2092

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.0448430), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Likely pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
3	-	-	Hereditary cancer-predisposing syndrome (3)
3	-	-	not provided (3)
2	-	-	Colorectal cancer, hereditary nonpolyposis, type 2 (2)
1	-	-	Hereditary nonpolyposis colorectal neoplasms (1)
1	-	-	Lynch syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.42
CADD	Pathogenic	33
DANN	Uncertain	0.99
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		9.5
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.8
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DL_spliceai		1.0		Position offset: -1

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

Other links and lift over

dbSNP: rs267607718; hg19: chr3-37038201; COSMIC: COSV51613936;