NM_006415.4:c.929C>G

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 1P and 5B. PP3BS1_SupportingBS2

The NM_006415.4(SPTLC1):​c.929C>G​(p.Ala310Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000614 in 1,613,574 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000062 ( 1 hom. )

Consequence

SPTLC1
NM_006415.4 missense

Scores

3
8
7

Clinical Significance

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

Conservation

PhyloP100: 7.78

Publications

4 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_benign. The variant received -4 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.837
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.0000526 (8/152108) while in subpopulation NFE AF = 0.000103 (7/68032). AF 95% confidence interval is 0.0000476. There are 0 homozygotes in GnomAd4. There are 1 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High AC in GnomAd4 at 8 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SPTLC1NM_006415.4 linkc.929C>G p.Ala310Gly missense_variant Exon 10 of 15 ENST00000262554.7 NP_006406.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SPTLC1ENST00000262554.7 linkc.929C>G p.Ala310Gly missense_variant Exon 10 of 15 1 NM_006415.4 ENSP00000262554.2

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152108
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.000103
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000796
AC:
20
AN:
251104
AF XY:
0.000118
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:
0.000123
Gnomad OTH exome
AF:
0.000653
GnomAD4 exome
AF:
0.0000623
AC:
91
AN:
1461466
Hom.:
1
Cov.:
30
AF XY:
0.0000715
AC XY:
52
AN XY:
727050
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33460
American (AMR)
AF:
0.0000224
AC:
1
AN:
44708
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39672
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86224
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53406
Middle Eastern (MID)
AF:
0.00139
AC:
8
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000675
AC:
75
AN:
1111718
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60384
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.478
Heterozygous variant carriers
0
6
12
18
24
30
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000526
AC:
8
AN:
152108
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74296
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41406
American (AMR)
AF:
0.0000655
AC:
1
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4818
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10600
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000103
AC:
7
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.519
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000164
Hom.:
0
Bravo
AF:
0.0000642
ExAC
AF:
0.0000906
AC:
11
EpiCase
AF:
0.000164
EpiControl
AF:
0.000178

ClinVar

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

Submissions by phenotype

Charcot-Marie-Tooth disease Uncertain:1
Inherited Neuropathy Consortium
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:literature only

Neuropathy, hereditary sensory and autonomic, type 1A Uncertain:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

not provided Uncertain:1
Dec 21, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported in an individual with sensory axonal neuropathy; however, the patient was adopted so inheritance could not be determined (PMID: 22302274); 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: 26681808, 25141825, 22302274)

Hereditary sensory and autonomic neuropathy type 1 Uncertain:1
Jan 13, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with glycine, which is neutral and non-polar, at codon 310 of the SPTLC1 protein (p.Ala310Gly). This variant is present in population databases (rs768841574, gnomAD 0.01%). This missense change has been observed in individual(s) with hereditary sensory and autonomic neuropathy (PMID: 22302274). ClinVar contains an entry for this variant (Variation ID: 526710). 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 not expected to disrupt SPTLC1 protein function with a negative predictive value of 80%. 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.

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.19
BayesDel_addAF
Benign
-0.028
T
BayesDel_noAF
Uncertain
-0.050
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.83
D
Eigen
Benign
0.10
Eigen_PC
Benign
0.16
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
D
M_CAP
Benign
0.058
D
MetaRNN
Pathogenic
0.84
D
MetaSVM
Uncertain
0.48
D
MutationAssessor
Benign
2.0
M
PhyloP100
7.8
PrimateAI
Benign
0.46
T
PROVEAN
Uncertain
-2.8
D
REVEL
Uncertain
0.52
Sift
Uncertain
0.010
D
Sift4G
Uncertain
0.010
D
Vest4
0.67
ClinPred
0.21
T
GERP RS
4.2
Varity_R
0.22
gMVP
0.86
Mutation Taster
=48/52
disease causing

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: rs768841574; hg19: chr9-94809950; API