rs1554706430

Variant names:

• chr9-92047241-A-T
• rs1554706430
• NM_006415.4:c.1012T>A

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2 PP3_Strong PP5

The NM_006415.4(SPTLC1):​c.1012T>A​(p.Ser338Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SPTLC1 NM_006415.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 9.01

Genes affected

SPTLC1 (HGNC:11277): (serine palmitoyltransferase long chain base subunit 1) This gene encodes a member of the class-II pyridoxal-phosphate-dependent aminotransferase family. The encoded protein is the long chain base subunit 1 of serine palmitoyltransferase. Serine palmitoyltransferase converts L-serine and palmitoyl-CoA to 3-oxosphinganine with pyridoxal 5'-phosphate and is the key enzyme in sphingolipid biosynthesis. Mutations in this gene were identified in patients with hereditary sensory neuropathy type 1. Alternatively spliced variants encoding different isoforms have been identified. Pseudogenes of this gene have been defined on chromosomes 1, 6, 10, and 13. [provided by RefSeq, Jul 2013]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.961
• PP5: Variant 9-92047241-A-T is Pathogenic according to our data. Variant chr9-92047241-A-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 456599.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SPTLC1	NM_006415.4	c.1012T>A	p.Ser338Thr	missense_variant	Exon 11 of 15	ENST00000262554.7	NP_006406.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SPTLC1	ENST00000262554.7	c.1012T>A	p.Ser338Thr	missense_variant	Exon 11 of 15	1	NM_006415.4	ENSP00000262554.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary sensory and autonomic neuropathy type 1 Pathogenic:1

Dec 02, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine, which is neutral and polar, with threonine, which is neutral and polar, at codon 338 of the SPTLC1 protein (p.Ser338Thr). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with clinical features of hereditary sensory neuropathy (internal data). ClinVar contains an entry for this variant (Variation ID: 456599). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on SPTLC1 protein function. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Inborn genetic diseases Uncertain:1

Jul 29, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.S338T variant (also known as c.1012T>A), located in coding exon 11 of the SPTLC1 gene, results from a T to A substitution at nucleotide position 1012. The serine at codon 338 is replaced by threonine, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.34
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.82	D
Eigen	Pathogenic	0.88
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.91	D
M_CAP	Pathogenic	0.54	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.2	M
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-2.6	D
REVEL	Pathogenic	0.90
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.86
MutPred		0.84		Gain of helix (P = 0.0696);
MVP		0.89
MPC		1.0
ClinPred		0.99	D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.89
gMVP		0.98

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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

Other links and lift over

dbSNP: rs1554706430; hg19: chr9-94809523;