14-75018979-C-T

Variant names:

• chr14-75018979-C-T
• rs1555386745
• NM_001040108.2:c.4092G>A

Variant summary

Our verdict is Benign. The variant received -8 ACMG points: 2P and 10B. PM2 BP4 BP6_Very_Strong BP7

The NM_001040108.2(MLH3):​c.4092G>A​(p.Gly1364Gly) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,782 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. G1364G) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MLH3 NM_001040108.2 splice_region, synonymous
• Scores: Splicing: ADA: 0.003708
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: 0.265
• Publications: 0 publications found

Genes affected

MLH3 (HGNC:7128): (mutL homolog 3) This gene is a member of the MutL-homolog (MLH) family of DNA mismatch repair (MMR) genes. MLH genes are implicated in maintaining genomic integrity during DNA replication and after meiotic recombination. The protein encoded by this gene functions as a heterodimer with other family members. Somatic mutations in this gene frequently occur in tumors exhibiting microsatellite instability, and germline mutations have been linked to hereditary nonpolyposis colorectal cancer type 7 (HNPCC7). Several alternatively spliced transcript variants have been identified, but the full-length nature of only two transcript variants has been determined. [provided by RefSeq, Jul 2008]

MLH3 Gene-Disease associations (from GenCC):

• colorectal cancer, hereditary nonpolyposis, type 7

  Inheritance: AD, AR Classification: MODERATE, LIMITED Submitted by: Ambry Genetics, ClinGen, Laboratory for Molecular Medicine
• intestinal polyposis syndrome

  Inheritance: AR Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Benign. The variant received -8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (REVEL=0.208).
• BP6: Variant 14-75018979-C-T is Benign according to our data. Variant chr14-75018979-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 478041.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=0.265 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001040108.2. 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
	MLH3	NM_001040108.2	MANE Select	c.4092G>A	p.Gly1364Gly	splice_region synonymous	Exon 12 of 13	NP_001035197.1	Q9UHC1-1
	MLH3	NM_014381.3		c.4020G>A	p.Gly1340Gly	splice_region synonymous	Exon 11 of 12	NP_055196.2	Q9UHC1-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MLH3	ENST00000355774.7	TSL:5 MANE Select	c.4092G>A	p.Gly1364Gly	splice_region synonymous	Exon 12 of 13	ENSP00000348020.2	Q9UHC1-1
	MLH3	ENST00000380968.6	TSL:1	c.4020G>A	p.Gly1340Gly	splice_region synonymous	Exon 11 of 12	ENSP00000370355.3	Q9UHC1-2
	MLH3	ENST00000930871.1		c.4092G>A	p.Gly1364Gly	splice_region synonymous	Exon 12 of 13	ENSP00000600930.1

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461782 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727202

African (AFR) AF: 0.0000299 AC: 1 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111924

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 30

ClinVar

ClinVar submissions

Significance: Likely benign

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	-	2	Colorectal cancer, hereditary nonpolyposis, type 7 (2)
-	-	1	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.36
CADD	Benign	12
DANN	Benign	0.81
PhyloP100		0.27

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0037
dbscSNV1_RF	Benign	0.074
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: rs1555386745; hg19: chr14-75485682;