14-77557151-A-T

Variant names:

• chr14-77557151-A-T
• rs199867946
• NM_004863.4:c.851-5T>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_004863.4(SPTLC2):​c.851-5T>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 33)
• Consequence: SPTLC2 NM_004863.4 splice_region, intron
• Scores: Splicing: ADA: 0.8192
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.75
• Publications: 0 publications found

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

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. Scorers claiming Benign: dbscSNV1_ADA.

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.851-5T>A		splice_region intron	N/A	NP_004854.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SPTLC2	ENST00000216484.7	TSL:1 MANE Select	c.851-5T>A		splice_region intron	N/A	ENSP00000216484.2
	SPTLC2	ENST00000554901.1	TSL:1	c.659-5T>A		splice_region intron	N/A	ENSP00000452189.1
	SPTLC2	ENST00000554365.1	TSL:2	n.171T>A		non_coding_transcript_exon	Exon 1 of 3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.86
CADD	Benign	19
DANN	Benign	0.45
PhyloP100		1.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.82
dbscSNV1_RF	Pathogenic	0.74
SpliceAI score (max)		0.84		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.84		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs199867946; hg19: chr14-78023494;