rs143757018

Positions:

chr14-77552203-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PP3_ModerateBS1_SupportingBS2

The NM_004863.4(SPTLC2):c.1196G>A(p.Arg399Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000254 in 1,613,978 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00014 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

SPTLC2
NM_004863.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 7.91

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 links:

SPTLC2 (HGNC:):

SPTLC2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.93

BS1

Variant frequency is greater than expected in population amr. gnomad4 allele frequency = 0.000138 (21/152162) while in subpopulation AMR AF= 0.000655 (10/15276). AF 95% confidence interval is 0.000354. There are 0 homozygotes in gnomad4. There are 12 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

BS2

High AC in GnomAd4 at 21 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SPTLC2	NM_004863.4 linkuse as main transcript	c.1196G>A	p.Arg399Gln	missense_variant	9/12	ENST00000216484.7	NP_004854.1	O15270A0A024R6H1
SPTLC2	XM_011537384.3 linkuse as main transcript	c.1196G>A	p.Arg399Gln	missense_variant	9/10		XP_011535686.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SPTLC2	ENST00000216484.7 linkuse as main transcript	c.1196G>A	p.Arg399Gln	missense_variant	9/12	1	NM_004863.4	ENSP00000216484.2		O15270

Frequencies

GnomAD3 genomes

AF:

0.000138

AC:

AN:

152162

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000217

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000655

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000193

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

GnomAD3 exomes

AF:

0.0000279

AC:

AN:

251164

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135746

show subpopulations

Gnomad AFR exome

AF:

0.000123

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000137

AC:

AN:

1461816

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

727200

show subpopulations

Gnomad4 AFR exome

AF:

0.000119

Gnomad4 AMR exome

AF:

0.0000894

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000719

Gnomad4 OTH exome

AF:

0.0000497

GnomAD4 genome

AF:

0.000138

AC:

AN:

152162

Hom.:

Cov.:

AF XY:

0.000161

AC XY:

AN XY:

74320

show subpopulations

Gnomad4 AFR

AF:

0.000217

Gnomad4 AMR

AF:

0.000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000193

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000702

Hom.:

Bravo

AF:

0.000317

ESP6500AA

AF:

0.000681

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000494

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.000119

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Neuropathy, hereditary sensory and autonomic, type 1C

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 15, 2024

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 399 of the SPTLC2 protein (p.Arg399Gln). This variant is present in population databases (rs143757018, gnomAD 0.01%). 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: 471487). 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

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 05, 2022

The p.R399Q variant (also known as c.1196G>A), located in coding exon 9 of the SPTLC2 gene, results from a G to A substitution at nucleotide position 1196. The arginine at codon 399 is replaced by glutamine, an amino acid with highly 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

Benign

0.15

BayesDel_addAF

Pathogenic

0.35

BayesDel_noAF

Pathogenic

0.44

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.93

Eigen

Pathogenic

0.98

Eigen_PC

Pathogenic

0.90

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.90

M_CAP

Pathogenic

0.31

MetaRNN

Pathogenic

0.93

MetaSVM

Pathogenic

0.99

MutationAssessor

Pathogenic

3.1

PrimateAI

Uncertain

0.69

PROVEAN

Uncertain

-3.6

REVEL

Pathogenic

0.81

Sift

Uncertain

0.0010

Sift4G

Uncertain

0.0040

Polyphen

1.0

Vest4

0.90

MVP

0.89

MPC

1.4

ClinPred

0.97

GERP RS

5.7

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.73

gMVP

0.92

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.080

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over