NM_004863.4:c.70G>C

Variant names:

• chr14-77616510-C-G
• rs1555379648
• NM_004863.4:c.70G>C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_004863.4(SPTLC2):​c.70G>C​(p.Glu24Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000145 in 1,382,214 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SPTLC2 NM_004863.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 3.27

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.1993767).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SPTLC2	NM_004863.4	c.70G>C	p.Glu24Gln	missense_variant	Exon 1 of 12	ENST00000216484.7	NP_004854.1
SPTLC2	XM_011537384.3	c.70G>C	p.Glu24Gln	missense_variant	Exon 1 of 10		XP_011535686.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SPTLC2	ENST00000216484.7	c.70G>C	p.Glu24Gln	missense_variant	Exon 1 of 12	1	NM_004863.4	ENSP00000216484.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000145 AC: 2 AN: 1382214 Hom.: 0 Cov.: 31 AF XY: 0.00000147 AC XY: 1 AN XY: 682258

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000186

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Neuropathy, hereditary sensory and autonomic, type 1C Uncertain:1

Jun 04, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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: 538847). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. 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. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamic acid, which is acidic and polar, with glutamine, which is neutral and polar, at codon 24 of the SPTLC2 protein (p.Glu24Gln). -

not provided Uncertain:1

Aug 27, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.086
BayesDel_addAF	Uncertain	0.022	T
BayesDel_noAF	Benign	-0.21
CADD	Benign	20
DANN	Uncertain	0.98
DEOGEN2	Benign	0.13	T
Eigen	Benign	-0.40
Eigen_PC	Benign	-0.21
FATHMM_MKL	Benign	0.72	D
LIST_S2	Benign	0.72	T
M_CAP	Pathogenic	0.85	D
MetaRNN	Benign	0.20	T
MetaSVM	Benign	-0.49	T
MutationAssessor	Benign	0.0	N
PrimateAI	Pathogenic	0.92	D
PROVEAN	Benign	0.080	N
REVEL	Benign	0.22
Sift	Benign	0.42	T
Sift4G	Benign	0.58	T
Polyphen		0.0	B
Vest4		0.18
MutPred		0.34		Gain of catalytic residue at Y29 (P = 7e-04);
MVP		0.22
MPC		0.54
ClinPred		0.18	T
GERP RS		3.3
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.0
Varity_R		0.13
gMVP		0.52

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

LitVar

Other links and lift over

dbSNP: rs1555379648; hg19: chr14-78082853;