Genetic Variant SMPD3:p.Asp429Asn (chr16-68370897-C-T) – ACMG Classification: Benign (-8 pts)

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_StrongBS2

The NM_018667.4(SMPD3):c.1285G>A(p.Asp429Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000836 in 1,614,058 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000085 ( 3 hom. )

Consequence

SMPD3
NM_018667.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.0490

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 Benign. Variant got -8 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.052097708).

BS2

High Homozygotes in GnomAdExome4 at 3 gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMPD3	NM_018667.4 link	c.1285G>A	p.Asp429Asn	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.1285G>A	p.Asp429Asn	missense_variant	Exon 3 of 9	1	NM_018667.4	ENSP00000219334.5		Q9NY59-1

Frequencies

GnomAD3 genomes

AF:

0.0000723

AC:

AN:

152214

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00115

Gnomad SAS

AF:

0.000828

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000104

AC:

AN:

250600

Hom.:

AF XY:

0.000125

AC XY:

AN XY:

135546

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000327

Gnomad SAS exome

AF:

0.000622

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000883

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000848

AC:

124

AN:

1461726

Hom.:

Cov.:

AF XY:

0.000103

AC XY:

AN XY:

727144

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000353

Gnomad4 SAS exome

AF:

0.000870

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000252

Gnomad4 OTH exome

AF:

0.0000994

GnomAD4 genome

AF:

0.0000722

AC:

AN:

152332

Hom.:

Cov.:

AF XY:

0.0000940

AC XY:

AN XY:

74482

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00116

Gnomad4 SAS

AF:

0.000829

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000227

ExAC

AF:

0.0000741

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Jul 10, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1285G>A (p.D429N) 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 1285, causing the aspartic acid (D) at amino acid position 429 to be replaced by an asparagine (N). 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

0.073

BayesDel_addAF

Benign

-0.56

BayesDel_noAF

Benign

-0.69

CADD

Benign

6.0

DANN

Benign

0.79

DEOGEN2

Benign

0.32

T;T;.

Eigen

Benign

-1.5

Eigen_PC

Benign

-1.6

FATHMM_MKL

Benign

0.044

LIST_S2

Uncertain

0.93

D;D;D

M_CAP

Benign

0.0072

MetaRNN

Benign

0.052

T;T;T

MetaSVM

Benign

-0.98

MutationAssessor

Benign

0.34

N;.;N

PrimateAI

Benign

0.29

PROVEAN

Benign

-1.4

N;N;N

REVEL

Benign

0.0040

Sift

Benign

0.097

T;T;T

Sift4G

Benign

0.11

T;T;T

Polyphen

0.0070

B;.;.

Vest4

0.12

MutPred

0.35

Gain of helix (P = 0.0199);Gain of helix (P = 0.0199);Gain of helix (P = 0.0199);

MVP

0.39

MPC

0.20

ClinPred

0.063

GERP RS

-6.9

Varity_R

0.13

gMVP

0.33

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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