chr14-75014613-T-C

Position:

• chr14-75014613-T-C

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_Strong BS2

The NM_001040108.2(MLH3):​c.*2469A>G variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000451 in 204,128 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 (★).

• Frequency:
  • Genomes: 𝑓 0.00045 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00046 (0 hom.)
• Consequence: MLH3 NM_001040108.2 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.845

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]

ACMG classification

Verdict is Benign. Variant got -8 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.92).
• BS2: High AC in GnomAd4 at 68 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MLH3	NM_001040108.2	c.*2469A>G		3_prime_UTR_variant	13/13	ENST00000355774.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MLH3	ENST00000355774.7	c.*2469A>G		3_prime_UTR_variant	13/13	5	NM_001040108.2	P1
MLH3	ENST00000380968.6	c.*2469A>G		3_prime_UTR_variant	12/12	1

Frequencies

GnomAD3 genomes AF: 0.000447 AC: 68 AN: 152214 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000724

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00144

Gnomad EAS AF: 0.000385

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.000659

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000750

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.000463 AC: 24 AN: 51796 Hom.: 0 Cov.: 0 AF XY: 0.000542 AC XY: 13 AN XY: 23994

Gnomad4 AFR exome AF: 0.000434

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.000613

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.000540

Gnomad4 OTH exome AF: 0.000923

GnomAD4 genome AF: 0.000446 AC: 68 AN: 152332 Hom.: 0 Cov.: 32 AF XY: 0.000349 AC XY: 26 AN XY: 74498

Gnomad4 AFR AF: 0.0000721

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00144

Gnomad4 EAS AF: 0.000386

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.000659

Gnomad4 NFE AF: 0.000750

Gnomad4 OTH AF: 0.00

Alfa AF: 0.00116 Hom.: 0

Bravo AF: 0.000336

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Colorectal cancer, hereditary nonpolyposis, type 7 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.92
CADD	Benign	0.64
DANN	Benign	0.30

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

Publications

LitVar

Other links and lift over

dbSNP: rs764557856; hg19: chr14-75481316;