2-142956235-T-A

Position:

chr2-142956235-T-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The ENST00000264170.9(KYNU):c.468T>A(p.Tyr156Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000573 in 1,604,298 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 Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000058 ( 0 hom. )

Consequence

KYNU
ENST00000264170.9 stop_gained

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: -0.0400

Variant links:

Genes affected

KYNU (HGNC:6469): (kynureninase) Kynureninase is a pyridoxal-5'-phosphate (pyridoxal-P) dependent enzyme that catalyzes the cleavage of L-kynurenine and L-3-hydroxykynurenine into anthranilic and 3-hydroxyanthranilic acids, respectively. Kynureninase is involved in the biosynthesis of NAD cofactors from tryptophan through the kynurenine pathway. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2010]

KYNU links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 2-142956235-T-A is Pathogenic according to our data. Variant chr2-142956235-T-A is described in ClinVar as [Pathogenic]. Clinvar id is 403730.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-142956235-T-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KYNU	NM_003937.3 linkuse as main transcript	c.468T>A	p.Tyr156Ter	stop_gained	6/14	ENST00000264170.9	NP_003928.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KYNU	ENST00000264170.9 linkuse as main transcript	c.468T>A	p.Tyr156Ter	stop_gained	6/14	1	NM_003937.3	ENSP00000264170	P1	Q16719-1

Frequencies

GnomAD3 genomes

AF:

0.0000526

AC:

AN:

152172

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.0000942

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000882

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000719

AC:

AN:

250318

Hom.:

AF XY:

0.000111

AC XY:

AN XY:

135328

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

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:

0.000159

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000578

AC:

AN:

1452126

Hom.:

Cov.:

AF XY:

0.0000609

AC XY:

AN XY:

723080

show subpopulations

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:

0.00

Gnomad4 FIN exome

AF:

0.0000565

Gnomad4 NFE exome

AF:

0.0000643

Gnomad4 OTH exome

AF:

0.000167

GnomAD4 genome

AF:

0.0000526

AC:

AN:

152172

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74332

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.0000942

Gnomad4 NFE

AF:

0.0000882

Gnomad4 OTH

AF:

0.000478

Bravo

AF:

0.0000453

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.000140

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.0000593

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Vertebral, cardiac, renal, and limb defects syndrome 2

Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Mar 06, 2024

- -

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Nov 17, 2024

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 28792876, 24463508, 31589614, 34200361, 38698835) -

Congenital NAD deficiency disorder

Pathogenic:1

Pathogenic, criteria provided, single submitter

research

Embryology Laboratory, Victor Chang Cardiac Research Institute

Dec 23, 2016

This variant was discovered in a North American family. The patient presented multiple congenital malformations affecting vertebrae, heart, kidney among others. This variant is a protein truncating variant and extremely rare (ExAC MAF 0.0001419). The patient is compound heterzygous for this variant and another protein truncating variant in the same KYNU gene (NM_003937.2:c.1045_1051delTTTAAGC). Her unaffected parents are heterzygous for only one variant. Enzyme assay confirmed that the protein product of this gene variant has lost enzyme activity. Mouse embryos homozygous null for Kynu presented similar phenotype as observed in the patient, and also showed reduced concentration of NAD in the embryonic tissue. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.37

BayesDel_noAF

Pathogenic

0.54

CADD

Pathogenic

DANN

Uncertain

0.99

Eigen

Benign

-0.16

Eigen_PC

Benign

-0.40

FATHMM_MKL

Uncertain

0.84

MutationTaster

Benign

1.0

A;A;A

Vest4

0.90

GERP RS

-1.8

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

Details are displayed if max score is > 0.2

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over