rs375224040

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_000543.5(SMPD1):​c.211G>A​(p.Ala71Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000366 in 1,614,170 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A71A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000039 ( 0 hom. )

Consequence

SMPD1
NM_000543.5 missense

Scores

1
16

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 1.05
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.07304296).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
SMPD1NM_000543.5 linkuse as main transcriptc.211G>A p.Ala71Thr missense_variant 1/6 ENST00000342245.9

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
SMPD1ENST00000342245.9 linkuse as main transcriptc.211G>A p.Ala71Thr missense_variant 1/61 NM_000543.5 P3P17405-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152160
Hom.:
0
Cov.:
33
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:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000358
AC:
9
AN:
251348
Hom.:
0
AF XY:
0.0000368
AC XY:
5
AN XY:
135876
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000792
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000390
AC:
57
AN:
1461892
Hom.:
0
Cov.:
38
AF XY:
0.0000344
AC XY:
25
AN XY:
727248
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000486
Gnomad4 OTH exome
AF:
0.0000497
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152278
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74452
show subpopulations
Gnomad4 AFR
AF:
0.00
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:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000189
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000576
AC:
7
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Niemann-Pick disease, type A;C0268243:Niemann-Pick disease, type B Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsOct 31, 2018- -
Uncertain significance, criteria provided, single submitterclinical testingInvitaeAug 26, 2021This sequence change replaces alanine with threonine at codon 71 of the SMPD1 protein (p.Ala71Thr). The alanine residue is weakly conserved and there is a small physicochemical difference between alanine and threonine. This variant is present in population databases (rs375224040, ExAC 0.01%). This variant has not been reported in the literature in individuals affected with SMPD1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Sphingomyelin/cholesterol lipidosis Uncertain:1
Uncertain significance, no assertion criteria providedclinical testingNatera, Inc.Sep 16, 2020- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.078
BayesDel_addAF
Benign
-0.40
T
BayesDel_noAF
Benign
-0.62
CADD
Benign
12
DANN
Uncertain
0.99
Eigen
Benign
-0.79
Eigen_PC
Benign
-0.81
FATHMM_MKL
Benign
0.18
N
LIST_S2
Benign
0.56
T;T
M_CAP
Benign
0.0025
T
MetaRNN
Benign
0.073
T;T
MetaSVM
Benign
-0.94
T
MutationTaster
Benign
1.0
N;N;N;N
PrimateAI
Benign
0.35
T
PROVEAN
Benign
0.050
N;N
REVEL
Benign
0.080
Sift
Benign
0.064
T;T
Sift4G
Benign
0.21
T;T
Vest4
0.039
MVP
0.35
MPC
0.23
ClinPred
0.13
T
GERP RS
-0.23
Varity_R
0.049
gMVP
0.46

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.

Other links and lift over

dbSNP: rs375224040; hg19: chr11-6412039; API