rs398123474

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1PM2PP5_Moderate

The NM_000543.5(SMPD1):​c.1092-1G>A variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,398 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

Frequency

Genomes: not found (cov: 31)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

SMPD1
NM_000543.5 splice_acceptor, intron

Scores

7
1
6
Splicing: ADA: 1.000
2

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 9.48

Publications

0 publications found
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 Gene-Disease associations (from GenCC):
  • acid sphingomyelinase deficiency
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • Niemann-Pick disease
    Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
  • Niemann-Pick disease type A
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, G2P
  • Niemann-Pick disease type B
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 12 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 11-6393215-G-A is Pathogenic according to our data. Variant chr11-6393215-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 4081802.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SMPD1NM_000543.5 linkc.1092-1G>A splice_acceptor_variant, intron_variant Intron 2 of 5 ENST00000342245.9 NP_000534.3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SMPD1ENST00000342245.9 linkc.1092-1G>A splice_acceptor_variant, intron_variant Intron 2 of 5 1 NM_000543.5 ENSP00000340409.4

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461398
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727000
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44708
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86220
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53396
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111646
Other (OTH)
AF:
0.00
AC:
0
AN:
60358
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
31

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Acid sphingomyelinase deficiency Pathogenic:1
Jun 17, 2025
Myriad Genetics, Inc.
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

NM_000543.4(SMPD1):c.1092-1G>A is a variant in a canonical splice site classified as likely pathogenic in the context of Niemann-Pick disease, SMPD1-related. c.1092-1G>A has not been observed in cases with relevant disease. Relevant functional assessments of this variant are not available in the literature. c.1092-1G>A has not been observed in referenced population frequency databases. In summary, NM_000543.4(SMPD1):c.1092-1G>A is a variant in a canonical splice site in a gene where loss of function is a known mechanism of disease and is predicted to disrupt protein function. Please note: this variant was assessed in the context of healthy population screening.

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.62
D
BayesDel_noAF
Pathogenic
0.35
CADD
Pathogenic
31
DANN
Uncertain
1.0
DEOGEN2
Benign
0.0
.;.
Eigen
Pathogenic
1.2
Eigen_PC
Pathogenic
1.0
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Benign
0.0
.;.
MetaRNN
Benign
0.0
.;.
MutationAssessor
Benign
0.0
.;.
PhyloP100
9.5
PROVEAN
Benign
0.0
.;.
REVEL
Benign
0.0
Sift
Pathogenic
0.0
.;.
Sift4G
Pathogenic
0.0
.;.
Vest4
0.0
GERP RS
5.2
Mutation Taster
=2/98
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.93
SpliceAI score (max)
0.91
Details are displayed if max score is > 0.2
DS_AL_spliceai
0.91
Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs398123474; hg19: chr11-6414445; API