Genetic Variant SMPD3:p.Met416Ile (chr16-68370934-C-T) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

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

The NM_018667.4(SMPD3):c.1248G>A(p.Met416Ile) variant causes a missense change. The variant allele was found at a frequency of 0.000209 in 1,614,074 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000099 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00022 ( 0 hom. )

Consequence

SMPD3
NM_018667.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.70

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 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMPD3	NM_018667.4 link	c.1248G>A	p.Met416Ile	missense_variant	Exon 3 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.1248G>A	p.Met416Ile	missense_variant	Exon 3 of 9	1	NM_018667.4	ENSP00000219334.5		Q9NY59-1

Frequencies

GnomAD3 genomes

AF:

0.0000985

AC:

AN:

152232

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000482

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:

0.0000941

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000176

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000135

AC:

AN:

251112

Hom.:

AF XY:

0.000140

AC XY:

AN XY:

135782

show subpopulations

Gnomad AFR exome

AF:

0.0000616

Gnomad AMR exome

AF:

0.0000868

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.000185

Gnomad NFE exome

AF:

0.000220

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.000221

AC:

323

AN:

1461842

Hom.:

Cov.:

AF XY:

0.000221

AC XY:

161

AN XY:

727218

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000671

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.000169

Gnomad4 NFE exome

AF:

0.000265

Gnomad4 OTH exome

AF:

0.000248

GnomAD4 genome

AF:

0.0000985

AC:

AN:

152232

Hom.:

Cov.:

AF XY:

0.0000672

AC XY:

AN XY:

74378

show subpopulations

Gnomad4 AFR

AF:

0.0000482

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.0000941

Gnomad4 NFE

AF:

0.000176

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000237

Hom.:

Bravo

AF:

0.000117

TwinsUK

AF:

0.000270

AC:

ALSPAC

AF:

0.00

AC:

ExAC

AF:

0.000165

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.000415

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Aug 09, 2021

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1248G>A (p.M416I) alteration is located in exon 3 (coding exon 1) of the SMPD3 gene. This alteration results from a G to A substitution at nucleotide position 1248, causing the methionine (M) at amino acid position 416 to be replaced by an isoleucine (I). 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

Uncertain

0.54

BayesDel_addAF

Benign

-0.32

BayesDel_noAF

Benign

-0.40

CADD

Uncertain

DANN

Uncertain

0.99

DEOGEN2

Benign

0.20

T;T;.

Eigen

Benign

0.089

Eigen_PC

Uncertain

0.26

FATHMM_MKL

Uncertain

0.95

LIST_S2

Uncertain

0.93

D;D;D

M_CAP

Benign

0.0056

MetaRNN

Uncertain

0.49

T;T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

0.69

N;.;N

PrimateAI

Benign

0.45

PROVEAN

Benign

-0.25

N;N;N

REVEL

Benign

0.065

Sift

Uncertain

0.026

D;D;D

Sift4G

Uncertain

0.020

D;D;D

Polyphen

0.17

B;.;.

Vest4

0.76

MutPred

0.46

Loss of helix (P = 0.0017);Loss of helix (P = 0.0017);Loss of helix (P = 0.0017);

MVP

0.13

MPC

0.23

ClinPred

0.050

GERP RS

5.4

Varity_R

0.36

gMVP

0.44

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