rs778545351

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_StrongPM2

The NM_004387.4(NKX2-5):​c.890_891dupTC​(p.Gly298fs) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000822 in 1,460,700 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

NKX2-5
NM_004387.4 frameshift

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: -0.981
Variant links:
Genes affected
NKX2-5 (HGNC:2488): (NK2 homeobox 5) This gene encodes a homeobox-containing transcription factor. This transcription factor functions in heart formation and development. Mutations in this gene cause atrial septal defect with atrioventricular conduction defect, and also tetralogy of Fallot, which are both heart malformation diseases. Mutations in this gene can also cause congenital hypothyroidism non-goitrous type 5, a non-autoimmune condition. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Oct 2009]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 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. There are 13 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 Protein UniProt
NKX2-5NM_004387.4 linkuse as main transcriptc.890_891dupTC p.Gly298fs frameshift_variant 2/2 ENST00000329198.5 NP_004378.1 P52952-1A0A0S2Z383
NKX2-5NM_001166176.2 linkuse as main transcriptc.*689_*690dupTC 3_prime_UTR_variant 2/2 NP_001159648.1 P52952-2
NKX2-5NM_001166175.2 linkuse as main transcriptc.*843_*844dupTC 3_prime_UTR_variant 2/2 NP_001159647.1 P52952-3A0A0S2Z3K2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
NKX2-5ENST00000329198.5 linkuse as main transcriptc.890_891dupTC p.Gly298fs frameshift_variant 2/21 NM_004387.4 ENSP00000327758.4 P52952-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.0000480
AC:
12
AN:
250164
Hom.:
0
AF XY:
0.0000369
AC XY:
5
AN XY:
135610
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000347
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:
0.00
GnomAD4 exome
AF:
0.00000822
AC:
12
AN:
1460700
Hom.:
0
Cov.:
34
AF XY:
0.00000688
AC XY:
5
AN XY:
726516
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000268
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:
0.00
GnomAD4 genome
Cov.:
32
Bravo
AF:
0.0000227

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpJun 10, 2019Variant summary: NKX2-5 c.890_891dupTC (p.Gly298SerfsX4) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. 5/5 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 4.8e-05 in 250164 control chromosomes. The observed variant frequency is approximately 9 fold of the estimated maximal expected allele frequency for a pathogenic variant in NKX2-5 causing Congenital Heart Disease phenotype (5e-06), suggesting that the variant is benign. To our knowledge, no occurrence of c.890_891dupTC in individuals affected with Congenital Heart Disease and no experimental evidence demonstrating its impact on protein function have been reported. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation and classified the variant as uncertain significance. Due to the conflicting evidence outlined above, the variant was classified as uncertain significance. -
Atrial septal defect 7 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpDec 09, 2023This sequence change creates a premature translational stop signal (p.Gly298Serfs*4) in the NKX2-5 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 27 amino acid(s) of the NKX2-5 protein. This variant is present in population databases (rs778545351, gnomAD 0.04%). This variant has not been reported in the literature in individuals affected with NKX2-5-related conditions. ClinVar contains an entry for this variant (Variation ID: 520891). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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. -
Tetralogy of Fallot;C1857586:Conotruncal heart malformations;C2673630:Hypothyroidism, congenital, nongoitrous, 5;C3276096:Atrial septal defect 7;C3280785:Ventricular septal defect 3;C3280795:Hypoplastic left heart syndrome 2 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsNov 04, 2021- -
Cardiovascular phenotype Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsFeb 12, 2024The c.890_891dupTC variant, located in coding exon 2 of the NKX2-5 gene, results from a duplication of TC at nucleotide position 890, causing a translational frameshift with a predicted alternate stop codon (p.G298Sfs*4). This alteration occurs at the 3' terminus of theNKX2-5 gene, is not expected to trigger nonsense-mediated mRNAdecay, and only impacts the last 8% of the protein. The exact functional effect of this alteration is unknown. Based on the available evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

Splicing

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.

Other links and lift over

dbSNP: rs778545351; hg19: chr5-172659655; API