20-13117541-T-G

Position:

• chr20-13117541-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_018327.4(SPTLC3):​c.968T>G​(p.Ile323Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SPTLC3 NM_018327.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.95

Genes affected

SPTLC3 (HGNC:16253): (serine palmitoyltransferase long chain base subunit 3) This gene encodes a subunit of the serine palmitoyltransferase complex which catalyzes the rate-limiting step in sphingolipid biosynthesis. This subunit metabolizes lauroyl- and myristoyl-CoA and generates C14 and C16-sphingoid bases. [provided by RefSeq, Mar 2017]

TASP1 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.879

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SPTLC3	NM_018327.4	c.968T>G	p.Ile323Arg	missense_variant	8/12	ENST00000399002.7	NP_060797.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SPTLC3	ENST00000399002.7	c.968T>G	p.Ile323Arg	missense_variant	8/12	1	NM_018327.4	ENSP00000381968	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 29, 2022

The c.968T>G (p.I323R) alteration is located in exon 8 (coding exon 8) of the SPTLC3 gene. This alteration results from a T to G substitution at nucleotide position 968, causing the isoleucine (I) at amino acid position 323 to be replaced by an arginine (R). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.28
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	0.0
CADD	Pathogenic	28
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.64	D
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.80
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.97	D
M_CAP	Pathogenic	0.33	D
MetaRNN	Pathogenic	0.88	D
MetaSVM	Uncertain	0.75	D
MutationAssessor	Uncertain	2.3	M
MutationTaster	Benign	1.0	D;D
PrimateAI	Benign	0.33	T
PROVEAN	Pathogenic	-6.2	D
REVEL	Pathogenic	0.77
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		0.99	D
Vest4		0.66
MutPred		0.64		Gain of MoRF binding (P = 0.0055);
MVP		0.88
MPC		0.83
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.86
gMVP		0.87

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr20-13098188;