2-15402288-AT-A

Variant summary

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

The NM_015909.4(NBAS):​c.2950del​(p.Ile984LeufsTer8) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000257 in 1,613,392 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.00016 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00027 ( 0 hom. )

Consequence

NBAS
NM_015909.4 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 2.51
Variant links:
Genes affected
NBAS (HGNC:15625): (NBAS subunit of NRZ tethering complex) This gene encodes a protein with two leucine zipper domains, a ribosomal protein S14 signature domain and a Sec39 like domain. The protein is thought to be involved in Golgi-to-ER transport. Mutations in this gene are associated with short stature, optic nerve atrophy, and Pelger-Huet anomaly. [provided by RefSeq, Oct 2012]

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 2-15402288-AT-A is Pathogenic according to our data. Variant chr2-15402288-AT-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 501319.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-15402288-AT-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
NBASNM_015909.4 linkuse as main transcriptc.2950del p.Ile984LeufsTer8 frameshift_variant 26/52 ENST00000281513.10 NP_056993.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
NBASENST00000281513.10 linkuse as main transcriptc.2950del p.Ile984LeufsTer8 frameshift_variant 26/521 NM_015909.4 ENSP00000281513 P1A2RRP1-1

Frequencies

GnomAD3 genomes
AF:
0.000158
AC:
24
AN:
152108
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
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:
0.000309
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000108
AC:
27
AN:
251026
Hom.:
0
AF XY:
0.0000885
AC XY:
12
AN XY:
135668
show subpopulations
Gnomad AFR exome
AF:
0.000123
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:
0.000220
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000267
AC:
390
AN:
1461284
Hom.:
0
Cov.:
31
AF XY:
0.000271
AC XY:
197
AN XY:
726946
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.0000383
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.000327
Gnomad4 OTH exome
AF:
0.000414
GnomAD4 genome
AF:
0.000158
AC:
24
AN:
152108
Hom.:
0
Cov.:
32
AF XY:
0.000135
AC XY:
10
AN XY:
74294
show subpopulations
Gnomad4 AFR
AF:
0.0000724
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.000309
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000434
Hom.:
0
Bravo
AF:
0.000151
EpiCase
AF:
0.000164
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:5
Likely pathogenic, criteria provided, single submitterclinical testingGeneDxAug 29, 2023Frameshift 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; This variant is associated with the following publications: (PMID: 30609409, 31589614, 31980526, 31964843, 34386911, 31015584, 31761904) -
Pathogenic, criteria provided, single submitterclinical testingInstitute of Medical Genetics and Applied Genomics, University Hospital TübingenOct 23, 2020- -
Likely pathogenic, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Apr 26, 2017- -
Likely pathogenic, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenDec 01, 2022NBAS: PVS1, PM2:Supporting -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 29, 2024This sequence change creates a premature translational stop signal (p.Ile984Leufs*8) in the NBAS gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in NBAS are known to be pathogenic (PMID: 26073778, 26541327, 27789416, 28031453). This variant is present in population databases (rs776797592, gnomAD 0.03%). This premature translational stop signal has been observed in individual(s) with NBAS-related disorders (PMID: 31761904). ClinVar contains an entry for this variant (Variation ID: 501319). For these reasons, this variant has been classified as Pathogenic. -
Acute infantile liver failure due to synthesis defect of mtDNA-encoded proteins Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpNov 02, 2023Variant summary: NBAS c.2950delA (p.Ile984LeufsX8) 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. Variants downstream of this position have been classified as pathogenic in ClinVar. The variant allele was found at a frequency of 0.00011 in 251026 control chromosomes (gnomAD). This frequency is not significantly higher than estimated for a pathogenic variant in NBAS causing Liver Failure Acute Infantile, Type 2 (0.00011 vs 0.0011), allowing no conclusion about variant significance. c.2950delA has been reported in the literature in individuals affected with NBAS-related disorders (example: Staufner_2020). The following publication has been ascertained in the context of this evaluation (PMID: 31761904). Six submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. All submitters classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Short stature-optic atrophy-Pelger-HuC+t anomaly syndrome;C3809651:Infantile liver failure syndrome 2 Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsApr 28, 2022- -
Infantile liver failure Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineSep 01, 2017The p.Ile984LeufsX8 variant in NBAS has not been reported in individuals with di sease and has been identified in 9/120,878 of chromosomes by the Exome Aggregati on Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs140841721). Althou gh this variant has been seen in the general population, its frequency is low en ough to be consistent with a recessive carrier frequency. This variant is predic ted to cause a frameshift, which alters the protein?s amino acid sequence beginn ing at position 984 and leads to a premature termination codon 8 amino acids dow nstream. This alteration is then predicted to lead to a truncated or absent prot ein. Homozygous or compound heterozygous mutations in NBAS have been associated with Infantile liver failure syndrome 2. In summary, this variant meets our cr iteria to be classified as pathogenic for Infantile liver failure syndrome 2 in an autosomal recessive manner based on low frequency in controls and functional prediction -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

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

LitVar

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

Other links and lift over

dbSNP: rs776797592; hg19: chr2-15542412; API