Genetic Variant SPTLC3:p.Arg349Gln (chr20-13117619-G-A) – ACMG Classification: Uncertain_significance (4 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_018327.4(SPTLC3):c.1046G>A(p.Arg349Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000242 in 1,613,944 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 Uncertain significance (★).

Frequency

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

Exomes 𝑓: 0.000024 ( 0 hom. )

Consequence

SPTLC3
NM_018327.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.92

Variant links:

Genes affected

SPTLC3 (HGNC:16253): (serine palmitoyltransferase long chain base subunit 3) This gene encodes a subunit of the serine palmitoyltransferase complex which catalyzes the rate-limiting step in sphingolipid biosynthesis. This subunit metabolizes lauroyl- and myristoyl-CoA and generates C14 and C16-sphingoid bases. [provided by RefSeq, Mar 2017]

SPTLC3 links:

TASP1 (HGNC:15859): (taspase 1) This gene encodes an endopeptidase that cleaves specific substrates following aspartate residues. The encoded protein undergoes posttranslational autoproteolytic processing to generate alpha and beta subunits, which reassemble into the active alpha2-beta2 heterotetramer. It is required to cleave MLL, a protein required for the maintenance of HOX gene expression, and TFIIA, a basal transcription factor. Alternatively spliced transcript variants have been described, but their biological validity has not been determined. [provided by RefSeq, Jul 2008]

TASP1 links:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.878

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SPTLC3	NM_018327.4 link	c.1046G>A	p.Arg349Gln	missense_variant	Exon 8 of 12	ENST00000399002.7	NP_060797.2	Q9NUV7-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SPTLC3	ENST00000399002.7 link	c.1046G>A	p.Arg349Gln	missense_variant	Exon 8 of 12	1	NM_018327.4	ENSP00000381968.2		Q9NUV7-1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152194

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:

0.000193

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000201

AC:

AN:

248858

Hom.:

AF XY:

0.0000222

AC XY:

AN XY:

134974

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000557

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000266

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000239

AC:

AN:

1461750

Hom.:

Cov.:

AF XY:

0.0000344

AC XY:

AN XY:

727182

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000504

Gnomad4 SAS exome

AF:

0.0000812

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000207

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152194

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74350

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000193

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.0000227

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Mar 23, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1046G>A (p.R349Q) alteration is located in exon 8 (coding exon 8) of the SPTLC3 gene. This alteration results from a G to A substitution at nucleotide position 1046, causing the arginine (R) at amino acid position 349 to be replaced by a glutamine (Q). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.12

BayesDel_addAF

Benign

-0.0029

BayesDel_noAF

Uncertain

-0.070

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.77

Eigen

Pathogenic

0.70

Eigen_PC

Uncertain

0.64

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.92

M_CAP

Pathogenic

0.29

MetaRNN

Pathogenic

0.88

MetaSVM

Pathogenic

1.0

MutationAssessor

Uncertain

2.7

PrimateAI

Benign

0.25

PROVEAN

Uncertain

-3.5

REVEL

Pathogenic

0.83

Sift

Uncertain

0.025

Sift4G

Uncertain

0.017

Polyphen

0.99

Vest4

0.42

MutPred

0.77

Loss of methylation at R349 (P = 0.0069);

MVP

0.81

MPC

0.36

ClinPred

0.96

GERP RS

4.2

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.56

gMVP

0.86

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.

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