chr14-77521572-C-T

Variant summary

Our verdict is Benign. The variant received -10 ACMG points: 0P and 10B. BP4BP6BS1BS2

The NM_004863.4(SPTLC2):​c.1313G>A​(p.Cys438Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000143 in 1,614,024 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign 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. C438R) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

SPTLC2
NM_004863.4 missense

Scores

1
8
10

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:1

Conservation

PhyloP100: 7.91

Publications

0 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: Benign. The variant received -10 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.26709533).
BP6
Variant 14-77521572-C-T is Benign according to our data. Variant chr14-77521572-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 471490.
BS1
Variant frequency is greater than expected in population amr. GnomAd4 allele frequency = 0.0000919 (14/152280) while in subpopulation AMR AF = 0.000588 (9/15302). AF 95% confidence interval is 0.000306. There are 0 homozygotes in GnomAd4. There are 8 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High AC in GnomAd4 at 14 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SPTLC2NM_004863.4 linkc.1313G>A p.Cys438Tyr missense_variant Exon 10 of 12 ENST00000216484.7 NP_004854.1 O15270A0A024R6H1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SPTLC2ENST00000216484.7 linkc.1313G>A p.Cys438Tyr missense_variant Exon 10 of 12 1 NM_004863.4 ENSP00000216484.2 O15270

Frequencies

GnomAD3 genomes
AF:
0.0000920
AC:
14
AN:
152162
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000121
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000589
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000199
AC:
5
AN:
251380
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.000185
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.00000616
AC:
9
AN:
1461744
Hom.:
0
Cov.:
32
AF XY:
0.00000275
AC XY:
2
AN XY:
727186
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33478
American (AMR)
AF:
0.0000894
AC:
4
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39690
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53386
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111918
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000919
AC:
14
AN:
152280
Hom.:
0
Cov.:
33
AF XY:
0.000107
AC XY:
8
AN XY:
74446
show subpopulations
African (AFR)
AF:
0.000120
AC:
5
AN:
41552
American (AMR)
AF:
0.000588
AC:
9
AN:
15302
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.561
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000967
Hom.:
0
Bravo
AF:
0.000264
ExAC
AF:
0.0000165
AC:
2
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

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

Submissions by phenotype

Neuropathy, hereditary sensory and autonomic, type 1C Uncertain:1
Jan 15, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces cysteine, which is neutral and slightly polar, with tyrosine, which is neutral and polar, at codon 438 of the SPTLC2 protein (p.Cys438Tyr). This variant is present in population databases (rs116342919, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with SPTLC2-related conditions. ClinVar contains an entry for this variant (Variation ID: 471490). 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%. 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. -

Inborn genetic diseases Benign:1
Apr 05, 2022
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.14
BayesDel_addAF
Benign
-0.077
T
BayesDel_noAF
Uncertain
-0.070
CADD
Uncertain
23
DANN
Benign
0.91
DEOGEN2
Benign
0.31
T
Eigen
Benign
-0.090
Eigen_PC
Benign
0.11
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.90
D
M_CAP
Uncertain
0.25
D
MetaRNN
Benign
0.27
T
MetaSVM
Uncertain
-0.22
T
MutationAssessor
Benign
-0.55
N
PhyloP100
7.9
PrimateAI
Uncertain
0.56
T
PROVEAN
Benign
-0.030
N
REVEL
Uncertain
0.52
Sift
Uncertain
0.0010
D
Sift4G
Uncertain
0.0030
D
Polyphen
0.047
B
Vest4
0.52
MVP
0.23
MPC
1.0
ClinPred
0.18
T
GERP RS
5.7
Varity_R
0.61
gMVP
0.91
Mutation Taster
=62/38
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs116342919; hg19: chr14-77987915; API