NM_001040108.2:c.666G>C

Variant names:

• chr14-75048990-C-G
• rs28756980
• NM_001040108.2:c.666G>C

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_001040108.2(MLH3):​c.666G>C​(p.Lys222Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,613,908 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 Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. K222K) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MLH3 NM_001040108.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.967
• Publications: 8 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

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.40783483).

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MLH3	NM_001040108.2	MANE Select	c.666G>C	p.Lys222Asn	missense	Exon 2 of 13	NP_001035197.1
	MLH3	NM_014381.3		c.666G>C	p.Lys222Asn	missense	Exon 2 of 12	NP_055196.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MLH3	ENST00000355774.7	TSL:5 MANE Select	c.666G>C	p.Lys222Asn	missense	Exon 2 of 13	ENSP00000348020.2
	MLH3	ENST00000380968.6	TSL:1	c.666G>C	p.Lys222Asn	missense	Exon 2 of 12	ENSP00000370355.3
	MLH3	ENST00000556257.5	TSL:5	c.666G>C	p.Lys222Asn	missense	Exon 2 of 7	ENSP00000451540.1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152174 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000196

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: 0.000478

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461734 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 727140

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44704

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86202

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

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111954

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152174 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74332

African (AFR) AF: 0.00 AC: 0 AN: 41432

American (AMR) AF: 0.000196 AC: 3 AN: 15272

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5198

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

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10606

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68048

Other (OTH) AF: 0.000478 AC: 1 AN: 2092

Alfa AF: 0.00 Hom.: 24

Bravo AF: 0.0000642

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

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

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.56
BayesDel_addAF	Benign	-0.064	T
BayesDel_noAF	Benign	-0.33
CADD	Benign	21
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.46	T
Eigen	Uncertain	0.32
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Benign	0.85	D
M_CAP	Benign	0.048	D
MetaRNN	Benign	0.41	T
MetaSVM	Uncertain	0.17	D
MutationAssessor	Benign	1.9	L
PhyloP100		0.97
PrimateAI	Uncertain	0.72	T
PROVEAN	Uncertain	-3.0	D
REVEL	Uncertain	0.47
Sift	Benign	0.031	D
Sift4G	Uncertain	0.018	D
Polyphen		0.97	D
Vest4		0.16
MutPred		0.45		Gain of catalytic residue at L223 (P = 0.0056)
MVP		0.88
MPC		0.34
ClinPred		0.98	D
GERP RS		3.8
Varity_R		0.58
gMVP		0.53
Mutation Taster		=68/32	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: rs28756980; hg19: chr14-75515693;