chr3-155828338-CCAGGGCTGTAA-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_ModeratePM2

The NM_004733.4(SLC33A1):​c.1511_1521delTTACAGCCCTG​(p.Val504fs) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,146 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000032 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

SLC33A1
NM_004733.4 frameshift

Scores

Not classified

Clinical Significance

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

Conservation

PhyloP100: 7.83
Variant links:
Genes affected
SLC33A1 (HGNC:95): (solute carrier family 33 member 1) The protein encoded by this gene is required for the formation of O-acetylated (Ac) gangliosides. The encoded protein is predicted to contain 6 to 10 transmembrane domains, and a leucine zipper motif in transmembrane domain III. Defects in this gene have been reported to cause spastic paraplegia autosomal dominant type 42 (SPG42) in one Chinese family, but not in similar patients of European descent. Two transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jul 2010]

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 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. Fraction of 0.0842 CDS is truncated, and there are 0 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
SLC33A1NM_004733.4 linkc.1511_1521delTTACAGCCCTG p.Val504fs frameshift_variant 6/6 ENST00000643144.2 NP_004724.1 O00400

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
SLC33A1ENST00000643144.2 linkc.1511_1521delTTACAGCCCTG p.Val504fs frameshift_variant 6/6 NM_004733.4 ENSP00000496241.1 O00400
ENSG00000284952ENST00000643876.1 linkn.*833_*843delTTACAGCCCTG non_coding_transcript_exon_variant 6/10 ENSP00000495323.1 A0A2R8Y6H1
ENSG00000284952ENST00000643876.1 linkn.*833_*843delTTACAGCCCTG 3_prime_UTR_variant 6/10 ENSP00000495323.1 A0A2R8Y6H1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152146
Hom.:
0
Cov.:
32
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000119
AC:
3
AN:
251198
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135822
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:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
Data not reliable, filtered out with message: AS_VQSR
AF:
0.0000316
AC:
46
AN:
1454972
Hom.:
0
AF XY:
0.0000290
AC XY:
21
AN XY:
724386
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:
0.00
Gnomad4 NFE exome
AF:
0.0000407
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152146
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74316
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:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000756

ClinVar

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

Submissions by phenotype

Spastic paraplegia Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpFeb 04, 2022This variant is present in population databases (rs772861569, gnomAD 0.002%). This sequence change creates a premature translational stop signal (p.Val504Glyfs*26) in the SLC33A1 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 46 amino acid(s) of the SLC33A1 protein. This variant has not been reported in the literature in individuals affected with SLC33A1-related conditions. ClinVar contains an entry for this variant (Variation ID: 418497). 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. -
Hereditary spastic paraplegia 42 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaSep 29, 2017The SLC33A1 c.1511_1521delTTACAGCCCTG (p.Val504GlyfsTer26) variant results in a frameshift and is predicted to result in premature termination of the protein. It was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018) and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score for this variant, it could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene and cDNA change, and amino acid change. No publications were found based on this search. Due to the potential impact of frameshift variants and the lack of clarifying evidence, this variant is classified as a variant of unknown significance but suspicious for pathogenicity for spastic paraplegia. -
Hereditary spastic paraplegia Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingGenome Diagnostics Laboratory, The Hospital for Sick ChildrenDec 01, 2019- -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingGeneDxOct 27, 2017The c.1511_1521del11 variant in the SLC33A1 gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. The c.1511_1521del11 variant causes a frameshift starting with codon Valine 504, changes this amino acid to a Glycine residue and creates a premature Stop codon at position 26 of the new reading frame, denoted p.Val504GlyfsX26. This variant is predicted to cause loss of normal protein function through protein truncation. The c.1511_1521del11 variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016). We interpret the c.1511_1521del11 variant as a variant of uncertain significance. -

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: rs772861569; hg19: chr3-155546127; API