rs119482083

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 12P and 4B. PP3_StrongPP5_Very_StrongBS2

The NM_006415.4(SPTLC1):​c.431T>A​(p.Val144Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000013 in 1,613,686 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

SPTLC1
NM_006415.4 missense

Scores

15
3
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:10O:1

Conservation

PhyloP100: 9.03

Publications

26 publications found
Variant links:
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]
SPTLC1 Gene-Disease associations (from GenCC):
  • amyotrophic lateral sclerosis 27, juvenile
    Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • neuropathy, hereditary sensory and autonomic, type 1A
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • hereditary sensory and autonomic neuropathy type 1
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.965
PP5
Variant 9-92068095-A-T is Pathogenic according to our data. Variant chr9-92068095-A-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 4801.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS2
High AC in GnomAdExome4 at 20 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SPTLC1NM_006415.4 linkc.431T>A p.Val144Asp missense_variant Exon 6 of 15 ENST00000262554.7 NP_006406.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SPTLC1ENST00000262554.7 linkc.431T>A p.Val144Asp missense_variant Exon 6 of 15 1 NM_006415.4 ENSP00000262554.2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152224
Hom.:
0
Cov.:
33
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
GnomAD2 exomes
AF:
0.00000799
AC:
2
AN:
250360
AF XY:
0.00000739
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000177
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000137
AC:
20
AN:
1461462
Hom.:
0
Cov.:
32
AF XY:
0.0000165
AC XY:
12
AN XY:
727010
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33468
American (AMR)
AF:
0.00
AC:
0
AN:
44702
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26122
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39632
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86228
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53340
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.0000180
AC:
20
AN:
1111836
Other (OTH)
AF:
0.00
AC:
0
AN:
60372
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152224
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74372
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41460
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000595

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:10Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Neuropathy, hereditary sensory and autonomic, type 1A Pathogenic:4Other:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
GeneReviews
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Mar 01, 2001
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

May 15, 2020
HudsonAlpha Institute for Biotechnology, HudsonAlpha Institute for Biotechnology
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

ACMG codes: PS3, PP3, PP5 -

Jul 20, 2021
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The SPTLC1 c.431T>A; p.Val144Asp variant (rs119482083) is reported in the literature in several individuals affected with hereditary sensory neuropathy (Dawkins 2001, Ho 2018). This variant is found on only two chromosomes in the Genome Aggregation Database (2/250360 alleles), indicating it is not a common polymorphism. The valine at codon 144 is highly conserved, and computational analyses predict that this variant is deleterious (REVEL: 0.921). Consistent with predictions, functional studies suggest the variant protein has reduced enzymatic activity and is associated with mitochondrial alterations (Hornemann 2009, Myers 2014, Stimpson 2014). Based on available information, this variant is considered to be likely pathogenic. References: Dawkins et al., Mutations in SPTLC1, encoding serine palmitoyltransferase, long chain base subunit-1, cause hereditary sensory neuropathy type I. Nat Genet. 2001 Mar;27(3):309-12. PMID 11242114. Ho and Jerath. V144D Mutation of SPTLC1 Can Present with Both Painful and Painless Phenotypes in Hereditary Sensory and Autonomic Neuropathies Type I. Case Rep Genet. 2018 Oct 18;2018:1898151. PMID: 30420926. Hornemann et al., A systematic comparison of all mutations in hereditary sensory neuropathy type I (HSAN I) reveals that the G387A mutation is not disease associated. Neurogenetics. 2009 Apr;10(2):135-43. PMID 19132419. Myers et al., Mutations in the SPTLC1 protein cause mitochondrial structural abnormalities and endoplasmic reticulum stress in lymphoblasts. DNA Cell Biol. 2014 Jul;33(7):399-407. PMID 24673574. Stimpson et al., Mitochondrial protein alterations in a familial peripheral neuropathy caused by the V144D amino acid mutation in the sphingolipid protein, SPTLC1. J Chem Biol. 2014 Nov 14;8(1):25-35. PMID 25584079. -

not provided Pathogenic:2
Jun 22, 2023
Athena Diagnostics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The frequency of this variant in the general population is consistent with pathogenicity (http://gnomad.broadinstitute.org). This variant has been identified in multiple unrelated individuals, and segregates with disease in at least one family with HSAN. Assessment of experimental evidence suggests this variant results in abnormal protein function. (PMID: 11781309, 19132419) -

May 15, 2025
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported in multiple individuals with hereditary neuropathy previously tested at GeneDx and in the published literature (PMID: 11242114, 32399692, 27164712); Protein expression studies show that p.(V144D) is associated with changes to the mitochondrial proteins and with structural changes to the mitochondria including electron dense and enlarged cristae (PMID: 24673574, 25584079); Published functional studies demonstrate a damaging effect on SPT activity and calcium regulation (PMID: 19132419, 34986032); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 30420926, 26681808, 25584079, 33497257, 34986032, 30778062, 34337561, 32730653, 15546589, 26395456, 24175284, 23454272, 30762923, 20920666, 32195206, 32399692, 20301564, 18348718, 25947379, 35895683, 35181405, 35904184, 35899376, 24711860, 20097765, 11781309, 8673084, 37509182, 36997154, 39901509, 24673574, 19132419, 11242114, 27164712) -

Charcot-Marie-Tooth disease Pathogenic:1
-
Molecular Genetics Laboratory, London Health Sciences Centre
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

SPTLC1-related disorder Pathogenic:1
Mar 14, 2024
PreventionGenetics, part of Exact Sciences
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

The SPTLC1 c.431T>A variant is predicted to result in the amino acid substitution p.Val144Asp. This variant has been reported in multiple individuals with hereditary sensory neuropathy (Table 2, Dawkins et al. 2001. PubMed ID: 11242114; Ho and Jerath. 2018. PubMed ID: 30420926; Table 1, Vogt et al. 2020. PubMed ID: 32399692). This variant is reported in 0.0018% of alleles in individuals of European (non-Finnish) descent in gnomAD. In vitro experimental studies suggest this variant decreases enzymatic activity of the protein and negatively regulates the BiP pathway (Hornemann et al. 2009. PubMed ID: 19132419; Myers et al. 2014. PubMed ID: 24673574). This variant is interpreted as pathogenic or likely pathogenic by multiple submitters to ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/4801/). In summary, this variant is interpreted as likely pathogenic. -

Inborn genetic diseases Pathogenic:1
Jan 19, 2022
Ambry Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.V144D variant (also known as c.431T>A), located in coding exon 6 of the SPTLC1 gene, results from a T to A substitution at nucleotide position 431. The valine at codon 144 is replaced by aspartic acid, an amino acid with highly dissimilar properties. The p.V144D alteration has been reported to co-segregate with disease in several families with sensory neuropathy (Nicholson GA et al. Nat. Genet., 1996 May;13:101-4; Dawkins JL et al. Nat. Genet., 2001 Mar;27:309-12; Ho KWD et al. Case Rep Genet, 2018 Oct;2018:1898151; Vogt B et al. J Neurol, 2020 Sep;267:2648-2654). The functional studies of V144D show an impact on mitochondrial structure and protein expression; however, a direct link to the mechanism of pathology is not clear and enzymatic activity studies are conflicting (Hornemann T et al. Neurogenetics, 2009 Apr;10:135-43; Myers SJ et al. DNA Cell Biol., 2014 Jul;33:399-407; Stimpson SE et al. J Chem Biol, 2015 Jan;8:25-35; Bode H et al. Hum. Mol. Genet., 2016 Mar;25:853-65). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Hereditary sensory and autonomic neuropathy type 1 Pathogenic:1
Dec 30, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 144 of the SPTLC1 protein (p.Val144Asp). This variant is present in population databases (rs119482083, gnomAD 0.002%). This missense change has been observed in individuals with hereditary sensory neuropathy (PMID: 11242114; internal data). ClinVar contains an entry for this variant (Variation ID: 4801). 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) indicates that this missense variant is expected to disrupt SPTLC1 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects SPTLC1 function (PMID: 11242114, 19132419, 24673574, 25584079, 26681808). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Pathogenic
0.49
D
BayesDel_noAF
Pathogenic
0.48
CADD
Pathogenic
28
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.91
D
Eigen
Pathogenic
0.78
Eigen_PC
Uncertain
0.66
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Uncertain
0.95
D
M_CAP
Pathogenic
0.71
D
MetaRNN
Pathogenic
0.97
D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
3.6
H
PhyloP100
9.0
PrimateAI
Pathogenic
0.85
D
PROVEAN
Pathogenic
-6.2
D
REVEL
Pathogenic
0.92
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.99
MVP
0.93
MPC
1.4
ClinPred
1.0
D
GERP RS
3.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.98
gMVP
0.98
Mutation Taster
=4/96
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs119482083; hg19: chr9-94830377; API