dbSNP rs147258619: SMPD1:p.Leu521Leu (chr11-6394272-C-T) – ACMG Classification: Benign (-8 pts)

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_ModerateBP6BP7BS2

The NM_000543.5(SMPD1):c.1561C>T(p.Leu521Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000587 in 1,614,230 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0031 ( 1 hom., cov: 33)

Exomes 𝑓: 0.00032 ( 2 hom. )

Consequence

SMPD1
NM_000543.5 synonymous

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:7

Conservation

PhyloP100: 2.46

Variant links:

Genes affected

SMPD1 (HGNC:11120): (sphingomyelin phosphodiesterase 1) The protein encoded by this gene is a lysosomal acid sphingomyelinase that converts sphingomyelin to ceramide. The encoded protein also has phospholipase C activity. Defects in this gene are a cause of Niemann-Pick disease type A (NPA) and Niemann-Pick disease type B (NPB). Multiple transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2010]

SMPD1 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 (BayesDel_noAF=-0.44).

BP6

Variant 11-6394272-C-T is Benign according to our data. Variant chr11-6394272-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 289949.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Benign=3, Uncertain_significance=1}. Variant chr11-6394272-C-T is described in Lovd as [Benign].

BP7

Synonymous conserved (PhyloP=2.46 with no splicing effect.

BS2

High Homozygotes in GnomAdExome4 at 2 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMPD1	NM_000543.5 link	c.1561C>T	p.Leu521Leu	synonymous_variant	Exon 6 of 6	ENST00000342245.9	NP_000534.3	P17405-1Q59EN6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMPD1	ENST00000342245.9 link	c.1561C>T	p.Leu521Leu	synonymous_variant	Exon 6 of 6	1	NM_000543.5	ENSP00000340409.4		P17405-1

Frequencies

GnomAD3 genomes

AF:

0.00315

AC:

479

AN:

152226

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0108

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00157

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:

0.00335

GnomAD3 exomes

AF:

0.000792

AC:

199

AN:

251340

Hom.:

AF XY:

0.000545

AC XY:

AN XY:

135818

show subpopulations

Gnomad AFR exome

AF:

0.0109

Gnomad AMR exome

AF:

0.000578

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000321

AC:

469

AN:

1461886

Hom.:

Cov.:

AF XY:

0.000265

AC XY:

193

AN XY:

727244

show subpopulations

Gnomad4 AFR exome

AF:

0.0114

Gnomad4 AMR exome

AF:

0.000760

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000270

Gnomad4 OTH exome

AF:

0.000811

GnomAD4 genome

AF:

0.00314

AC:

479

AN:

152344

Hom.:

Cov.:

AF XY:

0.00338

AC XY:

252

AN XY:

74504

show subpopulations

Gnomad4 AFR

AF:

0.0108

Gnomad4 AMR

AF:

0.00157

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:

0.00331

Alfa

AF:

0.00134

Hom.:

Bravo

AF:

0.00360

Asia WGS

AF:

0.000577

AC:

AN:

3478

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:7

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Benign:3

Aug 30, 2017

Mayo Clinic Laboratories, Mayo Clinic

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Mar 19, 2021

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jul 01, 2022

CeGaT Center for Human Genetics Tuebingen

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

SMPD1: BP4, BP7, BS1, BS2 -

Niemann-Pick disease, type A

Uncertain:1Benign:1

May 05, 2017

Natera, Inc.

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

not specified

Benign:1

Aug 26, 2016

Eurofins Ntd Llc (ga)

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

SMPD1-related disorder

Benign:1

Feb 25, 2019

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Niemann-Pick disease, type A;C0268243:Niemann-Pick disease, type B

Benign:1

Jan 15, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.44

CADD

Benign

5.1

DANN

Benign

0.71

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.11

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