4-107895676-A-G

Position:

• chr4-107895676-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_001375905.1(SGMS2):​c.123A>G​(p.Lys41=) variant causes a synonymous 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 Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: SGMS2 NM_001375905.1 synonymous
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.86

Genes affected

SGMS2 (HGNC:28395): (sphingomyelin synthase 2) Sphingomyelin, a major component of cell and Golgi membranes, is made by the transfer of phosphocholine from phosphatidylcholine onto ceramide, with diacylglycerol as a side product. The protein encoded by this gene is an enzyme that catalyzes this reaction primarily at the cell membrane. The synthesis is reversible, and this enzyme can catalyze the reaction in either direction. The encoded protein is required for cell growth. Three transcript variants encoding the same protein have been found for this gene. There is evidence for more variants, but the full-length nature of their transcripts has not been determined.[provided by RefSeq, Oct 2008]

CYP2U1-AS1 (HGNC:54817): (CYP2U1 and SGMS2 antisense RNA 1)

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SGMS2	NM_001375905.1	c.123A>G	p.Lys41=	synonymous_variant	3/7	ENST00000690982.1	NP_001362834.1
CYP2U1-AS1	NR_125929.1	n.150-2039T>C		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SGMS2	ENST00000690982.1	c.123A>G	p.Lys41=	synonymous_variant	3/7		NM_001375905.1	ENSP00000508566	P1
CYP2U1-AS1	ENST00000656249.1	n.290-2039T>C		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 30, 2023

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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. This variant has not been reported in the literature in individuals affected with SGMS2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change affects codon 41 of the SGMS2 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the SGMS2 protein. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.63
CADD	Benign	18
DANN	Benign	0.72

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.70		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.70		Position offset: -5

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr4-108816832;