NM_020442.6:c.1656T>A

Variant names:

• chr6-30921612-T-A
• rs2074511
• NM_020442.6:c.1656T>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_020442.6(VARS2):​c.1656T>A​(p.Val552Val) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. V552V) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: VARS2 NM_020442.6 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -2.45
• Publications: 0 publications found

Genes affected

VARS2 (HGNC:21642): (valyl-tRNA synthetase 2, mitochondrial) This gene encodes a mitochondrial aminoacyl-tRNA synthetase, which catalyzes the attachment of valine to tRNA(Val) for mitochondrial translation. Mutations in this gene cause combined oxidative phosphorylation deficiency-20, and are also associated with early-onset mitochondrial encephalopathies. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Aug 2014]

VARS2 Gene-Disease associations (from GenCC):

• mitochondrial disease

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• combined oxidative phosphorylation defect type 20

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)

ENSG00000288473 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.74).
• BP7: Synonymous conserved (PhyloP=-2.45 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
VARS2	NM_020442.6	c.1656T>A	p.Val552Val	synonymous_variant	Exon 18 of 30	ENST00000676266.1	NP_065175.4
VARS2	NM_001167734.2	c.1746T>A	p.Val582Val	synonymous_variant	Exon 18 of 30		NP_001161206.1
VARS2	NM_001167733.3	c.1236T>A	p.Val412Val	synonymous_variant	Exon 17 of 29		NP_001161205.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
VARS2	ENST00000676266.1	c.1656T>A	p.Val552Val	synonymous_variant	Exon 18 of 30		NM_020442.6	ENSP00000502585.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1455148 Hom.: 0 Cov.: 36 AF XY: 0.00 AC XY: 0 AN XY: 723198

African (AFR) AF: 0.00 AC: 0 AN: 33470

American (AMR) AF: 0.00 AC: 0 AN: 43520

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25876

East Asian (EAS) AF: 0.00 AC: 0 AN: 39556

South Asian (SAS) AF: 0.00 AC: 0 AN: 84780

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51630

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1110346

Other (OTH) AF: 0.00 AC: 0 AN: 60208

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.74
CADD	Benign	0.22
DANN	Benign	0.74
PhyloP100		-2.4
RBP_binding_hub_radar		1.0
RBP_regulation_power_radar		2.7

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: rs2074511; hg19: chr6-30889389;