NM_004863.4:c.1226C>T
Variant summary
Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BS2
The NM_004863.4(SPTLC2):c.1226C>T(p.Thr409Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000018 in 1,614,048 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T409K) has been classified as Uncertain significance.
Frequency
Consequence
NM_004863.4 missense
Scores
Clinical Significance
Conservation
Publications
- neuropathy, hereditary sensory and autonomic, type 1CInheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Ambry Genetics
- hereditary sensory and autonomic neuropathy type 1Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
Genome browser will be placed here
ACMG classification
Our verdict: Likely_benign. The variant received -4 ACMG points.
Variant Effect in Transcripts
ACMG analysis was done for transcript: NM_004863.4. You can select a different transcript below to see updated ACMG assignments.
RefSeq Transcripts
| Selected | Gene | Transcript | Tags | HGVSc | HGVSp | Effect | Exon Rank | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|---|
| SPTLC2 | NM_004863.4 | MANE Select | c.1226C>T | p.Thr409Met | missense | Exon 9 of 12 | NP_004854.1 |
Ensembl Transcripts
| Selected | Gene | Transcript | Tags | HGVSc | HGVSp | Effect | Exon Rank | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|---|
| SPTLC2 | ENST00000216484.7 | TSL:1 MANE Select | c.1226C>T | p.Thr409Met | missense | Exon 9 of 12 | ENSP00000216484.2 | ||
| SPTLC2 | ENST00000554901.1 | TSL:1 | c.1034C>T | p.Thr345Met | missense | Exon 8 of 9 | ENSP00000452189.1 | ||
| SPTLC2 | ENST00000554365.1 | TSL:2 | n.551C>T | non_coding_transcript_exon | Exon 3 of 3 |
Frequencies
GnomAD3 genomes AF: 0.0000197 AC: 3AN: 152198Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.00000796 AC: 2AN: 251206 AF XY: 0.00000737 show subpopulations
GnomAD4 exome AF: 0.0000178 AC: 26AN: 1461850Hom.: 0 Cov.: 32 AF XY: 0.0000151 AC XY: 11AN XY: 727222 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000197 AC: 3AN: 152198Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2AN XY: 74370 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
not specified Uncertain:1
A variant of uncertain significance has been identified in the SPTLC2 gene. The T409M variant has been reported as a pathogenic variant; however no additional information was provided (Astudillo et al.; Duan et al., 2015). Functions studies suggested that the T409M variant does not appear to be associated with HSAN1 and that it may be a benign variant (Bode et al., 2016). It was not observed with any significant frequency in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project. The T409M variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. In silico analysis predicts this variant is probably damaging to the protein structure/function. However, this substitution occurs at a position that is not conserved. Therefore, based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant.
Neuropathy, hereditary sensory and autonomic, type 1C Uncertain:1
This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 409 of the SPTLC2 protein (p.Thr409Met). This variant is present in population databases (rs368357970, gnomAD 0.004%). This missense change has been observed in individual(s) with amyotrophic lateral sclerosis (PMID: 36966328). ClinVar contains an entry for this variant (Variation ID: 373497). 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 have shown that this missense change does not substantially affect SPTLC2 function (PMID: 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:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at