12-123256877-T-G

Variant names:

• chr12-123256877-T-G
• rs374464556
• NM_152269.5:c.347T>G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_152269.5(MTRFR):​c.347T>G​(p.Val116Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,684 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V116I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MTRFR NM_152269.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.99
• Publications: 0 publications found

Genes affected

MTRFR (HGNC:26784): (mitochondrial translation release factor in rescue) This nuclear gene encodes a mitochondrial matrix protein that appears to contribute to peptide chain termination in the mitochondrial translation machinery. Two different 1 bp deletions (resulting in the same premature stop codon)result in decreased mitochondrial translation, decreased levels of oxidative phosphorylation complexes and encepthalomyopathy. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2010]

CDK2AP1 (HGNC:14002): (cyclin dependent kinase 2 associated protein 1) The protein encoded by this gene is a cyclin-dependent kinase 2 (CDK2) -associated protein which is thought to negatively regulate CDK2 activity by sequestering monomeric CDK2, and targeting CDK2 for proteolysis. This protein was found to also interact with DNA polymerase alpha/primase and mediate the phosphorylation of the large p180 subunit, which suggests a regulatory role in DNA replication during the S-phase of the cell cycle. This protein also forms a core subunit of the nucleosome remodeling and histone deacetylation (NURD) complex that epigenetically regulates embryonic stem cell differentiation. This gene thus plays a role in both cell-cycle and epigenetic regulation. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jul 2012]

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.871

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MTRFR	NM_152269.5	c.347T>G	p.Val116Gly	missense_variant	Exon 3 of 3	ENST00000253233.6	NP_689482.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MTRFR	ENST00000253233.6	c.347T>G	p.Val116Gly	missense_variant	Exon 3 of 3	1	NM_152269.5	ENSP00000253233.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000402 AC: 1 AN: 248760 AF XY: 0.00000742

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461684 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727158

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44714

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39688

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86250

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111858

Other (OTH) AF: 0.00 AC: 0 AN: 60384

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Spastic paraplegia;C3150801:Combined oxidative phosphorylation defect type 7 Uncertain:1

Jul 17, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is present in population databases (rs374464556, gnomAD 0.003%). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. ClinVar contains an entry for this variant (Variation ID: 2026403). This variant has not been reported in the literature in individuals affected with C12orf65-related conditions. This sequence change replaces valine, which is neutral and non-polar, with glycine, which is neutral and non-polar, at codon 116 of the C12orf65 protein (p.Val116Gly). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.62
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Pathogenic	0.14
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Benign	0.23	T;T;T;T
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Benign	0.85	.;D;D;.
M_CAP	Benign	0.027	D
MetaRNN	Pathogenic	0.87	D;D;D;D
MetaSVM	Benign	-0.97	T
MutationAssessor	Pathogenic	3.3	M;M;.;M
PhyloP100		8.0
PROVEAN	Pathogenic	-5.3	D;D;D;D
REVEL	Pathogenic	0.68
Sift	Uncertain	0.0020	D;D;D;D
Sift4G	Uncertain	0.0020	D;D;D;D
Polyphen		1.0	D;D;.;D
Vest4		0.61
MutPred		0.78		Loss of stability (P = 0.0069);Loss of stability (P = 0.0069);Loss of stability (P = 0.0069);Loss of stability (P = 0.0069);
MVP		0.48
MPC		0.34
ClinPred		0.98	D
GERP RS		5.9
Varity_R		0.95
gMVP		0.64
Mutation Taster		=53/47	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: rs374464556; hg19: chr12-123741424;