rs1300253311

Variant names:

• chr11-9998316-A-C
• rs1300253311
• NM_030962.4:c.925T>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_030962.4(SBF2):​c.925T>G​(p.Ser309Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,609,930 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SBF2 NM_030962.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.32
• Publications: 0 publications found

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]

SBF2 Gene-Disease associations (from GenCC):

• Charcot-Marie-Tooth disease type 4B2

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P, ClinGen, Ambry Genetics

ENSG00000286561 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SBF2	NM_030962.4	c.925T>G	p.Ser309Ala	missense_variant	Exon 9 of 40	ENST00000256190.13	NP_112224.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SBF2	ENST00000256190.13	c.925T>G	p.Ser309Ala	missense_variant	Exon 9 of 40	1	NM_030962.4	ENSP00000256190.8

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152256 Hom.: 0 Cov.: 33

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 AF: 0.00000137 AC: 2 AN: 1457674 Hom.: 0 Cov.: 28 AF XY: 0.00000138 AC XY: 1 AN XY: 725436

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33390

American (AMR) AF: 0.00 AC: 0 AN: 44706

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26100

East Asian (EAS) AF: 0.00 AC: 0 AN: 39624

South Asian (SAS) AF: 0.00 AC: 0 AN: 86078

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53352

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5750

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1108406

Other (OTH) AF: 0.00 AC: 0 AN: 60268

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152256 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74390

African (AFR) AF: 0.00 AC: 0 AN: 41472

American (AMR) AF: 0.00 AC: 0 AN: 15284

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5208

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10630

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68038

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Charcot-Marie-Tooth disease type 4 Uncertain:1

Sep 07, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine with alanine at codon 309 of the SBF2 protein (p.Ser309Ala). The serine residue is moderately conserved and there is a moderate physicochemical difference between serine and alanine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with SBF2-related disease. 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, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.085
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Benign	-0.090
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.14	T
Eigen	Uncertain	0.44
Eigen_PC	Uncertain	0.53
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.79	T
M_CAP	Uncertain	0.20	D
MetaRNN	Uncertain	0.63	D
MetaSVM	Uncertain	-0.069	T
MutationAssessor	Benign	1.8	L
PhyloP100		9.3
PrimateAI	Uncertain	0.69	T
PROVEAN	Benign	-0.71	N
REVEL	Uncertain	0.41
Sift	Benign	0.15	T
Sift4G	Benign	0.51	T
Polyphen		0.78	P
Vest4		0.57
MutPred		0.37		Loss of disorder (P = 0.0566);
MVP		0.85
MPC		0.17
ClinPred		0.85	D
GERP RS		5.4
Varity_R		0.10
gMVP		0.35
Mutation Taster		=62/38	polymorphism

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

Other links and lift over

dbSNP: rs1300253311; hg19: chr11-10019863;