rs1485497925

Positions:

• chr4-76174235-T-C
• chr4-76174235-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_005506.4(SCARB2):​c.903A>G​(p.Ile301Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SCARB2 NM_005506.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.26

Genes affected

SCARB2 (HGNC:1665): (scavenger receptor class B member 2) The protein encoded by this gene is a type III glycoprotein that is located primarily in limiting membranes of lysosomes and endosomes. Earlier studies in mice and rat suggested that this protein may participate in membrane transportation and the reorganization of endosomal/lysosomal compartment. The protein deficiency in mice was reported to impair cell membrane transport processes and cause pelvic junction obstruction, deafness, and peripheral neuropathy. Further studies in human showed that this protein is a ubiquitously expressed protein and that it is involved in the pathogenesis of HFMD (hand, foot, and mouth disease) caused by enterovirus-71 and possibly by coxsackievirus A16. Mutations in this gene caused an autosomal recessive progressive myoclonic epilepsy-4 (EPM4), also known as action myoclonus-renal failure syndrome (AMRF). Alternatively spliced transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Feb 2011]

SCARB2 (HGNC:):

ACMG classification

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=0.07780236).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SCARB2	NM_005506.4	c.903A>G	p.Ile301Met	missense_variant	7/12	ENST00000264896.8	NP_005497.1
SCARB2	NM_001204255.2	c.474A>G	p.Ile158Met	missense_variant	4/9		NP_001191184.1
SCARB2	XM_047416429.1	c.429A>G	p.Ile143Met	missense_variant	7/12		XP_047272385.1
SCARB2	XM_047416430.1	c.429A>G	p.Ile143Met	missense_variant	7/12		XP_047272386.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCARB2	ENST00000264896.8	c.903A>G	p.Ile301Met	missense_variant	7/12	1	NM_005506.4	ENSP00000264896.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461888 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727244

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000447

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Progressive myoclonic epilepsy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 23, 2023

Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt SCARB2 protein function. 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. ClinVar contains an entry for this variant (Variation ID: 462927). This variant has not been reported in the literature in individuals affected with SCARB2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces isoleucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 301 of the SCARB2 protein (p.Ile301Met). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.21	T
BayesDel_noAF	Benign	-0.54
CADD	Benign	14
DANN	Benign	0.76
DEOGEN2	Benign	0.14	T;.;.;.;.;.;.
Eigen	Benign	-0.83
Eigen_PC	Benign	-0.83
FATHMM_MKL	Benign	0.066	N
LIST_S2	Benign	0.77	T;T;T;T;T;T;T
M_CAP	Benign	0.024	T
MetaRNN	Benign	0.078	T;T;T;T;T;T;T
MetaSVM	Benign	-0.90	T
MutationAssessor	Benign	0.87	L;.;.;.;.;.;.
PrimateAI	Benign	0.45	T
PROVEAN	Benign	-0.90	N;.;.;.;.;N;.
REVEL	Benign	0.045
Sift	Benign	0.057	T;.;.;.;.;D;.
Sift4G	Benign	0.061	T;.;.;.;.;T;.
Polyphen		0.018	B;.;.;.;.;.;.
Vest4		0.15
MutPred		0.43		Gain of catalytic residue at V297 (P = 0.0297);.;Gain of catalytic residue at V297 (P = 0.0297);.;.;.;Gain of catalytic residue at V297 (P = 0.0297);
MVP		0.32
MPC		0.27
ClinPred		0.11	T
GERP RS		-0.39
Varity_R		0.25
gMVP		0.54

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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

Other links and lift over

dbSNP: rs1485497925; hg19: chr4-77095388; COSMIC: COSV53667807; COSMIC: COSV53667807;