14-75047857-C-A

Variant names:

• chr14-75047857-C-A
• rs28756984
• NM_001040108.2:c.1799G>T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001040108.2(MLH3):​c.1799G>T​(p.Arg600Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,476 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R600Q) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MLH3 NM_001040108.2 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.684
• 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: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.10945904).

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.1799G>T	p.Arg600Leu	missense	Exon 2 of 13	NP_001035197.1	Q9UHC1-1
	MLH3	NM_014381.3		c.1799G>T	p.Arg600Leu	missense	Exon 2 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.1799G>T	p.Arg600Leu	missense	Exon 2 of 13	ENSP00000348020.2	Q9UHC1-1
	MLH3	ENST00000380968.6	TSL:1	c.1799G>T	p.Arg600Leu	missense	Exon 2 of 12	ENSP00000370355.3	Q9UHC1-2
	MLH3	ENST00000930871.1		c.1799G>T	p.Arg600Leu	missense	Exon 2 of 13	ENSP00000600930.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460476 Hom.: 0 Cov.: 35 AF XY: 0.00000138 AC XY: 1 AN XY: 726426

African (AFR) AF: 0.00 AC: 0 AN: 33376

American (AMR) AF: 0.00 AC: 0 AN: 44490

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26108

East Asian (EAS) AF: 0.00 AC: 0 AN: 39684

South Asian (SAS) AF: 0.00 AC: 0 AN: 85630

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53390

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111694

Other (OTH) AF: 0.00 AC: 0 AN: 60340

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.22	T
BayesDel_noAF	Benign	-0.55
CADD	Benign	11
DANN	Uncertain	0.99
DEOGEN2	Benign	0.10	T
Eigen	Benign	-0.70
Eigen_PC	Benign	-0.61
FATHMM_MKL	Benign	0.19	N
LIST_S2	Benign	0.56	T
M_CAP	Benign	0.021	T
MetaRNN	Benign	0.11	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.1	L
PhyloP100		0.68
PrimateAI	Benign	0.20	T
PROVEAN	Benign	-1.3	N
REVEL	Benign	0.017
Sift	Benign	0.035	D
Sift4G	Uncertain	0.057	T
Polyphen		0.0020	B
Vest4		0.25
MutPred		0.51		Gain of catalytic residue at K602 (P = 0)
MVP		0.40
MPC		0.13
ClinPred		0.17	T
GERP RS		2.1
Varity_R		0.077
gMVP		0.36
Mutation Taster		=98/2	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
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: rs28756984; hg19: chr14-75514560;