chr14-77555401-C-T

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 3P and 4B. PP3_ModeratePP5BS2

The NM_004863.4(SPTLC2):​c.1075G>A​(p.Val359Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000041 in 1,461,894 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V359A) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

SPTLC2
NM_004863.4 missense

Scores

14
4
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:1

Conservation

PhyloP100: 7.80

Publications

7 publications found
Variant links:
Genes affected
SPTLC2 (HGNC:11278): (serine palmitoyltransferase long chain base subunit 2) This gene encodes a long chain base subunit of serine palmitoyltransferase. Serine palmitoyltransferase, which consists of two different subunits, is the key enzyme in sphingolipid biosynthesis. It catalyzes the pyridoxal-5-prime-phosphate-dependent condensation of L-serine and palmitoyl-CoA to 3-oxosphinganine. Mutations in this gene were identified in patients with hereditary sensory neuropathy type I. [provided by RefSeq, Mar 2011]
SPTLC2 Gene-Disease associations (from GenCC):
  • neuropathy, hereditary sensory and autonomic, type 1C
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Ambry Genetics
  • 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 -1 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.917
PP5
Variant 14-77555401-C-T is Pathogenic according to our data. Variant chr14-77555401-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 4798.
BS2
High AC in GnomAdExome4 at 6 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SPTLC2NM_004863.4 linkc.1075G>A p.Val359Met missense_variant Exon 8 of 12 ENST00000216484.7 NP_004854.1
SPTLC2XM_011537384.3 linkc.1075G>A p.Val359Met missense_variant Exon 8 of 10 XP_011535686.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SPTLC2ENST00000216484.7 linkc.1075G>A p.Val359Met missense_variant Exon 8 of 12 1 NM_004863.4 ENSP00000216484.2

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
0.00000410
AC:
6
AN:
1461894
Hom.:
0
Cov.:
32
AF XY:
0.00000413
AC XY:
3
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
1
2
2
3
4
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
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Neuropathy, hereditary sensory and autonomic, type 1C Pathogenic:2Uncertain:1
Oct 08, 2010
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Aug 13, 2021
MGZ Medical Genetics Center
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 16, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 359 of the SPTLC2 protein (p.Val359Met). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with hereditary sensory and autonomic neuropathy (PMID: 20920666). ClinVar contains an entry for this variant (Variation ID: 4798). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt SPTLC2 protein function with a negative predictive value of 80%. Experimental studies are conflicting or provide insufficient evidence to determine the effect of this variant on SPTLC2 function (PMID: 20920666, 24175284, 26681808). 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
Uncertain
0.56
BayesDel_addAF
Pathogenic
0.49
D
BayesDel_noAF
Pathogenic
0.46
CADD
Pathogenic
29
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.92
D
Eigen
Pathogenic
0.97
Eigen_PC
Pathogenic
0.87
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.98
D
M_CAP
Pathogenic
0.43
D
MetaRNN
Pathogenic
0.92
D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
3.0
M
PhyloP100
7.8
PrimateAI
Uncertain
0.63
T
PROVEAN
Uncertain
-2.8
D
REVEL
Pathogenic
0.89
Sift
Pathogenic
0.0
D
Sift4G
Uncertain
0.0020
D
Polyphen
1.0
D
Vest4
0.96
MutPred
0.60
Gain of catalytic residue at T355 (P = 4e-04);
MVP
0.93
MPC
1.4
ClinPred
0.99
D
GERP RS
4.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.90
gMVP
0.84
Mutation Taster
=40/60
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
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: rs267607090; hg19: chr14-78021744; API