rs875989834

Variant names:

• chr11-6394200-TACCGTGTGTACCA-T
• rs875989834
• NM_000543.5:c.1491_1503delCCGTGTGTACCAA

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PVS1 PP5

The NM_000543.5(SMPD1):​c.1491_1503delCCGTGTGTACCAA​(p.Tyr497fs) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type DEL_BIG, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SMPD1 NM_000543.5 frameshift
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 9.37
• 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: 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)

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 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 77 pathogenic variants in the truncated region.
• PP5: Variant 11-6394200-TACCGTGTGTACCA-T is Pathogenic according to our data. Variant chr11-6394200-TACCGTGTGTACCA-T is described in ClinVar as Pathogenic. ClinVar VariationId is 225622.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.1491_1503delCCGTGTGTACCAA	p.Tyr497fs	frameshift	Exon 6 of 6	NP_000534.3
	SMPD1	NM_001007593.3		c.1488_1500delCCGTGTGTACCAA	p.Tyr496fs	frameshift	Exon 6 of 6	NP_001007594.2
	SMPD1	NM_001365135.2		c.1359_1371delCCGTGTGTACCAA	p.Tyr453fs	frameshift	Exon 5 of 5	NP_001352064.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMPD1	ENST00000342245.9	TSL:1 MANE Select	c.1491_1503delCCGTGTGTACCAA	p.Tyr497fs	frameshift	Exon 6 of 6	ENSP00000340409.4
	SMPD1	ENST00000526280.1	TSL:1	c.546_558delCCGTGTGTACCAA	p.Tyr182fs	frameshift	Exon 4 of 4	ENSP00000436278.1
	SMPD1	ENST00000531303.5	TSL:1	n.*342_*354delCCGTGTGTACCAA		non_coding_transcript_exon	Exon 6 of 6	ENSP00000432625.1

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: 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
PhyloP100		9.4
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

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

Other links and lift over

dbSNP: rs875989834; hg19: chr11-6415430;