rs142433332

Positions:

• chr1-173831632-T-A
• chr1-173831632-T-C
• chr1-173831632-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_018122.5(DARS2):​c.492+2T>A variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000207 in 1,451,198 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: DARS2 NM_018122.5 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 5.46

Genes affected

DARS2 (HGNC:25538): (aspartyl-tRNA synthetase 2, mitochondrial) The protein encoded by this gene belongs to the class-II aminoacyl-tRNA synthetase family. It is a mitochondrial enzyme that specifically aminoacylates aspartyl-tRNA. Mutations in this gene are associated with leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL). [provided by RefSeq, Nov 2009]

DARS2 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.04901961 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DARS2	NM_018122.5	c.492+2T>A		splice_donor_variant, intron_variant		ENST00000649689.2	NP_060592.2
DARS2	NM_001365212.1	c.492+2T>A		splice_donor_variant, intron_variant			NP_001352141.1
DARS2	NM_001365213.2	c.492+2T>A		splice_donor_variant, intron_variant			NP_001352142.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DARS2	ENST00000649689.2	c.492+2T>A		splice_donor_variant, intron_variant			NM_018122.5	ENSP00000497569.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000797 AC: 2 AN: 251028 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135838

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000164

GnomAD4 exome AF: 0.00000207 AC: 3 AN: 1451198 Hom.: 0 Cov.: 28 AF XY: 0.00000415 AC XY: 3 AN XY: 722742

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000447

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000167

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.35
CADD	Pathogenic	27
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Pathogenic	0.99	D
GERP RS		5.8

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.99		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs142433332; hg19: chr1-173800770;