Genetic Variant SMPD3:p.Gly556Ser (chr16-68363539-C-T) – ACMG Classification: Uncertain_significance (1 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_018667.4(SMPD3):c.1666G>A(p.Gly556Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000235 in 1,613,786 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

SMPD3
NM_018667.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.44

Variant links:

Genes affected

SMPD3 (HGNC:14240): (sphingomyelin phosphodiesterase 3) Predicted to enable phosphatidic acid binding activity; phosphatidylserine binding activity; and sphingomyelin phosphodiesterase activity. Predicted to be involved in positive regulation of exosomal secretion and sphingomyelin metabolic process. Predicted to act upstream of or within several processes, including animal organ development; enzyme linked receptor protein signaling pathway; and sphingolipid metabolic process. Predicted to be located in Golgi apparatus and plasma membrane. Predicted to be active in cytoplasm. Biomarker of pulmonary emphysema. [provided by Alliance of Genome Resources, Apr 2022]

SMPD3 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.27698618).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMPD3	NM_018667.4 link	c.1666G>A	p.Gly556Ser	missense_variant	Exon 7 of 9	ENST00000219334.10	NP_061137.1	Q9NY59-1A8K0T6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMPD3	ENST00000219334.10 link	c.1666G>A	p.Gly556Ser	missense_variant	Exon 7 of 9	1	NM_018667.4	ENSP00000219334.5		Q9NY59-1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152130

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000724

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

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:

0.0000240

AC:

AN:

250448

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135430

show subpopulations

Gnomad AFR exome

AF:

0.00

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:

0.0000266

Gnomad OTH exome

AF:

0.000164

GnomAD4 exome

AF:

0.0000233

AC:

AN:

1461656

Hom.:

Cov.:

AF XY:

0.0000261

AC XY:

AN XY:

727122

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000504

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000225

Gnomad4 OTH exome

AF:

0.0000497

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152130

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74320

show subpopulations

Gnomad4 AFR

AF:

0.0000724

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.0000302

ExAC

AF:

0.0000330

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Jan 22, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1666G>A (p.G556S) alteration is located in exon 7 (coding exon 5) of the SMPD3 gene. This alteration results from a G to A substitution at nucleotide position 1666, causing the glycine (G) at amino acid position 556 to be replaced by a serine (S). 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

0.10

BayesDel_addAF

Benign

-0.21

BayesDel_noAF

Benign

-0.37

CADD

Benign

DANN

Benign

0.67

DEOGEN2

Benign

0.19

T;T;.

Eigen

Benign

-0.68

Eigen_PC

Benign

-0.64

FATHMM_MKL

Benign

0.42

LIST_S2

Uncertain

0.90

D;D;D

M_CAP

Benign

0.043

MetaRNN

Benign

0.28

T;T;T

MetaSVM

Benign

-0.92

MutationAssessor

Benign

2.0

M;.;.

PrimateAI

Benign

0.37

PROVEAN

Benign

-0.61

N;N;N

REVEL

Benign

0.13

Sift

Benign

0.53

T;T;T

Sift4G

Benign

0.42

T;T;T

Polyphen

0.12

B;.;.

Vest4

0.52

MutPred

0.38

Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);.;

MVP

0.45

MPC

0.26

ClinPred

0.023

GERP RS

1.8

Varity_R

0.039

gMVP

0.67

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

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