16-75627978-G-A

Variant names:

• chr16-75627978-G-A
• NM_005548.3:c.1711C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_005548.3(KARS1):​c.1711C>T​(p.Pro571Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000689 in 1,450,628 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: KARS1 NM_005548.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.97
• Publications: 0 publications found

Genes affected

KARS1 (HGNC:6215): (lysyl-tRNA synthetase 1) Aminoacyl-tRNA synthetases are a class of enzymes that charge tRNAs with their cognate amino acids. Lysyl-tRNA synthetase is a homodimer localized to the cytoplasm which belongs to the class II family of tRNA synthetases. It has been shown to be a target of autoantibodies in the human autoimmune diseases, polymyositis or dermatomyositis. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

KARS1 Gene-Disease associations (from GenCC):

• autosomal recessive nonsyndromic hearing loss 89

  Inheritance: AR Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), G2P
• leukoencephalopathy, progressive, infantile-onset, with or without deafness

  Inheritance: AR Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• Charcot-Marie-Tooth disease recessive intermediate B

  Inheritance: AR, Unknown Classification: SUPPORTIVE, LIMITED Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)
• hearing loss, autosomal recessive

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• nonsyndromic genetic hearing loss

  Inheritance: AR Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_005548.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.987

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KARS1	NM_005548.3	c.1711C>T	p.Pro571Ser	missense_variant	Exon 14 of 14	ENST00000302445.8	NP_005539.1
KARS1	NM_001130089.2	c.1795C>T	p.Pro599Ser	missense_variant	Exon 15 of 15		NP_001123561.1
KARS1	NM_001378148.1	c.1243C>T	p.Pro415Ser	missense_variant	Exon 14 of 14		NP_001365077.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KARS1	ENST00000302445.8	c.1711C>T	p.Pro571Ser	missense_variant	Exon 14 of 14	1	NM_005548.3	ENSP00000303043.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.89e-7 AC: 1 AN: 1450628 Hom.: 0 Cov.: 27 AF XY: 0.00000138 AC XY: 1 AN XY: 722500

African (AFR) AF: 0.0000301 AC: 1 AN: 33222

American (AMR) AF: 0.00 AC: 0 AN: 44706

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26070

East Asian (EAS) AF: 0.00 AC: 0 AN: 39658

South Asian (SAS) AF: 0.00 AC: 0 AN: 86038

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53410

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5746

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1101800

Other (OTH) AF: 0.00 AC: 0 AN: 59978

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Oct 29, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with serine, which is neutral and polar, at codon 599 of the KARS protein (p.Pro599Ser). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with KARS-related conditions. ClinVar contains an entry for this variant (Variation ID: 2732328). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt KARS protein function with a positive predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	31
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.86	.;D
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.50	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.6	.;H
PhyloP100		9.0
PrimateAI	Uncertain	0.65	T
PROVEAN	Pathogenic	-7.1	D;D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.86
MutPred		0.90		.;Loss of methylation at K574 (P = 0.0607);
MVP		0.99
MPC		0.50
ClinPred		1.0	D
GERP RS		6.0
Varity_R		0.95
gMVP		0.91
Mutation Taster		=9/91	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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

hg19: chr16-75661876;