11-6394202-C-G

Variant names:

• chr11-6394202-C-G
• rs1554935439
• NM_000543.5:c.1491C>G

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_000543.5(SMPD1):​c.1491C>G​(p.Tyr497*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SMPD1 NM_000543.5 stop_gained
• Clinical Significance: Likely pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 1.11
• Publications: 0 publications found

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: Orphanet, Genomics England PanelApp, PanelApp Australia, G2P
• Niemann-Pick disease type B

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Genomics England PanelApp, Orphanet, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 78 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-6394202-C-G is Pathogenic according to our data. Variant chr11-6394202-C-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 551123.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000543.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMPD1	NM_000543.5	MANE Select	c.1491C>G	p.Tyr497*	stop_gained	Exon 6 of 6	NP_000534.3
	SMPD1	NM_001007593.3		c.1488C>G	p.Tyr496*	stop_gained	Exon 6 of 6	NP_001007594.2	P17405-4
	SMPD1	NM_001365135.2		c.1359C>G	p.Tyr453*	stop_gained	Exon 5 of 5	NP_001352064.1	P17405-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMPD1	ENST00000342245.9	TSL:1 MANE Select	c.1491C>G	p.Tyr497*	stop_gained	Exon 6 of 6	ENSP00000340409.4	P17405-1
	SMPD1	ENST00000526280.1	TSL:1	c.546C>G	p.Tyr182*	stop_gained	Exon 4 of 4	ENSP00000436278.1	H0YEP5
	SMPD1	ENST00000531303.5	TSL:1	n.*342C>G		non_coding_transcript_exon	Exon 6 of 6	ENSP00000432625.1	E9PPK6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Likely pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Niemann-Pick disease, type A (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	37
DANN	Uncertain	1.0
Eigen	Uncertain	0.34
Eigen_PC	Benign	0.10
FATHMM_MKL	Uncertain	0.93	D
PhyloP100		1.1
Vest4		0.96
ClinPred		1.0	D
GERP RS		0.41
Mutation Taster		=3/197	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs1554935439; hg19: chr11-6415432;