rs770642379

Variant names:

Variant summary

Our verdict is Pathogenic. The variant received 20 ACMG points: 20P and 0B. PVS1PS3PP5_Very_Strong

The NM_003937.3(KYNU):c.1045_1051delTTTAAGC(p.Phe349LysfsTer4) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000969 in 1,609,320 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV000540923: 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." and additional evidence is available in ClinVar. Synonymous variant affecting the same amino acid position (i.e. F349F) has been classified as Benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00010 ( 0 hom. )

Consequence

KYNU
NM_003937.3 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 7.45

Publications

0 publications found

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 Gene-Disease associations (from GenCC):

vertebral, cardiac, renal, and limb defects syndrome 2
Inheritance: AR Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, ClinGen
encephalopathy due to hydroxykynureninuria
Inheritance: AR Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics
congenital vertebral-cardiac-renal anomalies syndrome
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

KYNU links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 20 ACMG points.

PVS1

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

PS3

PS3 evidence extracted from ClinVar submissions: SCV000540923: 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.; SCV000618083: Published functional studies demonstrate a damaging effect on enzyme activity (PMID: 28792876)

PP5

Variant 2-143040429-TCTTTAAG-T is Pathogenic according to our data. Variant chr2-143040429-TCTTTAAG-T is described in ClinVar as Pathogenic. ClinVar VariationId is 403731.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003937.3. 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
	KYNU	NM_003937.3	MANE Select	c.1045_1051delTTTAAGC	p.Phe349LysfsTer4	frameshift	Exon 13 of 14	NP_003928.1	Q16719-1
	KYNU	NM_001199241.2		c.1045_1051delTTTAAGC	p.Phe349LysfsTer4	frameshift	Exon 14 of 15	NP_001186170.1	Q16719-1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
KYNU	ENST00000264170.9	TSL:1 MANE Select	c.1045_1051delTTTAAGC	p.Phe349LysfsTer4	frameshift	Exon 13 of 14	ENSP00000264170.4	Q16719-1
KYNU	ENST00000409512.5	TSL:1	c.1045_1051delTTTAAGC	p.Phe349LysfsTer4	frameshift	Exon 14 of 15	ENSP00000386731.1	Q16719-1
KYNU	ENST00000852084.1		c.1171_1177delTTTAAGC	p.Phe391LysfsTer4	frameshift	Exon 14 of 15	ENSP00000522143.1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152042

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:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000588

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000319

AC:

AN:

250432

AF XY:

0.0000369

show subpopulations

Gnomad AFR exome

AF:

0.0000616

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000619

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000104

AC:

152

AN:

1457278

Hom.:

AF XY:

0.000106

AC XY:

AN XY:

725204

show subpopulations

African (AFR)

AF:

0.0000300

AC:

AN:

33364

American (AMR)

AF:

0.00

AC:

AN:

44580

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26072

East Asian (EAS)

AF:

0.00

AC:

AN:

39656

South Asian (SAS)

AF:

0.00

AC:

AN:

86156

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53300

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5752

European-Non Finnish (NFE)

AF:

0.000136

AC:

151

AN:

1108164

Other (OTH)

AF:

0.00

AC:

AN:

60234

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.444

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152042

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74272

show subpopulations

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

African (AFR)

AF:

0.00

AC:

AN:

41424

American (AMR)

AF:

0.00

AC:

AN:

15220

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5188

South Asian (SAS)

AF:

0.00

AC:

AN:

4818

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10616

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000588

AC:

AN:

67988

Other (OTH)

AF:

0.00

AC:

AN:

2090

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000000000000666134), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.400

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.0000302

ClinVar

ClinVar submissions

Significance:Pathogenic

Revision:criteria provided, multiple submitters, no conflicts

View on ClinVar

Pathogenic

VUS

Benign

Condition

Vertebral, cardiac, renal, and limb defects syndrome 2 (3)

Congenital NAD deficiency disorder (1)

not provided (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

PhyloP100

7.5

Mutation Taster

=2/198

disease causing (ClinVar)

(source)

Splicing

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

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over