2-222572002-G-A

Variant summary

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

The NM_005687.5(FARSB):c.1639C>T(p.Arg547Ter) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000274 in 1,459,768 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. R547R) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: FARSB NM_005687.5 stop_gained
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.29

Genes affected

FARSB (HGNC:17800): (phenylalanyl-tRNA synthetase subunit beta) This gene encodes a highly conserved enzyme that belongs to the aminoacyl-tRNA synthetase class IIc subfamily. This enzyme comprises the regulatory beta subunits that form a tetramer with two catalytic alpha subunits. In the presence of ATP, this tetramer is responsible for attaching L-phenylalanine to the terminal adenosine of the appropriate tRNA. A pseudogene located on chromosome 10 has been identified. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2015]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.074 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FARSB	NM_005687.5	c.1639C>T	p.Arg547Ter	stop_gained	17/17	ENST00000281828.8
FARSB	XM_006712169.3	c.1342C>T	p.Arg448Ter	stop_gained	18/18
FARSB	XM_011510466.3	c.1342C>T	p.Arg448Ter	stop_gained	18/18
FARSB	NR_130154.2	n.1854C>T		non_coding_transcript_exon_variant	18/18

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FARSB	ENST00000281828.8	c.1639C>T	p.Arg547Ter	stop_gained	17/17	1	NM_005687.5	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1459768 Hom.: 0 Cov.: 33 AF XY: 0.00000275 AC XY: 2 AN XY: 726130

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000117

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 05, 2022

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. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. This variant has not been reported in the literature in individuals affected with FARSB-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Arg547*) in the FARSB gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 43 amino acid(s) of the FARSB protein. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.60	D
BayesDel_noAF	Pathogenic	0.62
Cadd	Pathogenic	37
Dann	Uncertain	1.0
Eigen	Pathogenic	0.72
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	D;D
Vest4		0.32
GERP RS		3.8

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr2-223436721;