NM_020320.5:c.1674T>C

Variant names:

• chr6-87514476-A-G
• rs2127985729
• NM_020320.5:c.1674T>C

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_020320.5(RARS2):​c.1674T>C​(p.Ala558Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,128 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 Likely benign (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: RARS2 NM_020320.5 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.600
• Publications: 0 publications found

Genes affected

RARS2 (HGNC:21406): (arginyl-tRNA synthetase 2, mitochondrial) This nuclear gene encodes a protein that localizes to the mitochondria, where it catalyzes the transfer of L-arginine to its cognate tRNA, an important step in translation of mitochondrially-encoded proteins. Defects in this gene are a cause of pontocerebellar hypoplasia type 6 (PCH6). Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2016]

RARS2 Gene-Disease associations (from GenCC):

• mitochondrial disease

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• pontocerebellar hypoplasia type 6

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P, Laboratory for Molecular Medicine, Ambry Genetics
• complex neurodevelopmental disorder

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.51).
• BP6: Variant 6-87514476-A-G is Benign according to our data. Variant chr6-87514476-A-G is described in ClinVar as Likely_benign. ClinVar VariationId is 1549840.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=0.6 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_020320.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RARS2	NM_020320.5	MANE Select	c.1674T>C	p.Ala558Ala	synonymous	Exon 20 of 20	NP_064716.2	Q5T160
	RARS2	NM_001350505.2		c.1674T>C	p.Ala558Ala	synonymous	Exon 20 of 21	NP_001337434.1	A0A8I5KWC6
	RARS2	NM_001350506.2		c.1149T>C	p.Ala383Ala	synonymous	Exon 20 of 21	NP_001337435.1	A0A8I5KPZ0

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RARS2	ENST00000369536.10	TSL:1 MANE Select	c.1674T>C	p.Ala558Ala	synonymous	Exon 20 of 20	ENSP00000358549.5	Q5T160
	RARS2	ENST00000687437.1		c.1764T>C	p.Ala588Ala	synonymous	Exon 21 of 21	ENSP00000508968.1	A0A8I5KP51
	RARS2	ENST00000691725.1		c.1674T>C	p.Ala558Ala	synonymous	Exon 20 of 21	ENSP00000509453.1	A0A8I5KWC6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460128 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 726478

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33422

American (AMR) AF: 0.00 AC: 0 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26116

East Asian (EAS) AF: 0.00 AC: 0 AN: 39646

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86222

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53400

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1110506

Other (OTH) AF: 0.00 AC: 0 AN: 60334

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Likely benign

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	-	1	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.51
CADD	Benign	12
DANN	Benign	0.84
PhyloP100		0.60

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: rs2127985729; hg19: chr6-88224194; COSMIC: COSV106110781; COSMIC: COSV106110781;