rs201806063

Positions:

• chr11-9963865-C-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_030962.4(SBF2):​c.1618G>T​(p.Val540Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,292 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: SBF2 NM_030962.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 1.18

Genes affected

SBF2 (HGNC:2135): (SET binding factor 2) This gene encodes a pseudophosphatase and member of the myotubularin-related protein family. This gene maps within the CMT4B2 candidate region of chromosome 11p15 and mutations in this gene have been associated with Charcot-Marie-Tooth Disease, type 4B2. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.045171767).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SBF2	NM_030962.4	c.1618G>T	p.Val540Leu	missense_variant	15/40	ENST00000256190.13	NP_112224.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SBF2	ENST00000256190.13	c.1618G>T	p.Val540Leu	missense_variant	15/40	1	NM_030962.4	ENSP00000256190	P3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152174 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 25

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152292 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74470

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 16, 2021

The p.V540L variant (also known as c.1618G>T), located in coding exon 15 of the SBF2 gene, results from a G to T substitution at nucleotide position 1618. The valine at codon 540 is replaced by leucine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Athena Diagnostics

Nov 27, 2018

- -

Charcot-Marie-Tooth disease type 4 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 28, 2022

This variant is present in population databases (rs201806063, gnomAD 0.0009%). 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 missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. ClinVar contains an entry for this variant (Variation ID: 543349). This variant has not been reported in the literature in individuals affected with SBF2-related conditions. This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 540 of the SBF2 protein (p.Val540Leu). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Benign	-0.23	T
BayesDel_noAF	Benign	-0.57
CADD	Benign	19
DANN	Uncertain	0.98
DEOGEN2	Benign	0.058	T
Eigen	Benign	-0.36
Eigen_PC	Benign	-0.17
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Uncertain	0.91	D
M_CAP	Benign	0.0056	T
MetaRNN	Benign	0.045	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-0.55	N
MutationTaster	Benign	1.0	N
PrimateAI	Uncertain	0.51	T
PROVEAN	Benign	-0.18	N
REVEL	Benign	0.059
Sift	Benign	0.41	T
Sift4G	Benign	0.32	T
Polyphen		0.044	B
Vest4		0.13
MutPred		0.38		Loss of methylation at K539 (P = 0.0346);
MVP		0.28
MPC		0.19
ClinPred		0.14	T
GERP RS		4.7
Varity_R		0.041
gMVP		0.22

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: rs201806063; hg19: chr11-9985412;