chr14-75014492-A-G

Variant names:

• chr14-75014492-A-G
• rs138458771
• NM_001040108.2:c.*2590T>C

Variant summary

Our verdict is Benign. The variant received -14 ACMG points: 0P and 14B. BP4_Strong BP6_Moderate BS1 BS2

The NM_001040108.2(MLH3):​c.*2590T>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00373 in 190,568 control chromosomes in the GnomAD database, including 4 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.0044 (4 hom., cov: 32)
  • Exomes 𝑓: 0.0010 (0 hom.)
• Consequence: MLH3 NM_001040108.2 3_prime_UTR
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -1.70
• 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

ACMG classification

Our verdict: Benign. The variant received -14 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.93).
• BP6: Variant 14-75014492-A-G is Benign according to our data. Variant chr14-75014492-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 314350.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00441 (671/152264) while in subpopulation AFR AF = 0.0154 (638/41546). AF 95% confidence interval is 0.0144. There are 4 homozygotes in GnomAd4. There are 284 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
• BS2: High Homozygotes in GnomAd4 at 4 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MLH3	NM_001040108.2	c.*2590T>C		3_prime_UTR_variant	Exon 13 of 13	ENST00000355774.7	NP_001035197.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MLH3	ENST00000355774.7	c.*2590T>C		3_prime_UTR_variant	Exon 13 of 13	5	NM_001040108.2	ENSP00000348020.2
MLH3	ENST00000380968.6	c.*2590T>C		3_prime_UTR_variant	Exon 12 of 12	1		ENSP00000370355.3

Frequencies

GnomAD3 genomes AF: 0.00440 AC: 670 AN: 152146 Hom.: 4 Cov.: 32

Gnomad AFR AF: 0.0154

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00157

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: 0.0000441

Gnomad OTH AF: 0.00287

GnomAD4 exome AF: 0.00102 AC: 39 AN: 38304 Hom.: 0 Cov.: 0 AF XY: 0.000739 AC XY: 13 AN XY: 17594

African (AFR) AF: 0.0223 AC: 34 AN: 1522

American (AMR) AF: 0.00107 AC: 1 AN: 936

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 2416

East Asian (EAS) AF: 0.00 AC: 0 AN: 6856

South Asian (SAS) AF: 0.00 AC: 0 AN: 316

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 32

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 234

European-Non Finnish (NFE) AF: 0.0000439 AC: 1 AN: 22764

Other (OTH) AF: 0.000929 AC: 3 AN: 3228

GnomAD4 genome AF: 0.00441 AC: 671 AN: 152264 Hom.: 4 Cov.: 32 AF XY: 0.00381 AC XY: 284 AN XY: 74450

African (AFR) AF: 0.0154 AC: 638 AN: 41546

American (AMR) AF: 0.00157 AC: 24 AN: 15298

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5178

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10610

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000441 AC: 3 AN: 68020

Other (OTH) AF: 0.00284 AC: 6 AN: 2112

Alfa AF: 0.00249 Hom.: 1

Bravo AF: 0.00488

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Colorectal cancer, hereditary nonpolyposis, type 7 Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.93
CADD	Benign	0.12
DANN	Benign	0.31
PhyloP100		-1.7
Mutation Taster		=100/0	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: rs138458771; hg19: chr14-75481195;