rs79401259

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 0P and 7B. BP4_ModerateBS1_SupportingBS2

The NM_030962.4(SBF2):​c.5035C>T​(p.Arg1679Cys) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000134 in 1,613,712 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. 17/23 in silico tools predict a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. R1679R) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00014 ( 2 hom. )

Consequence

SBF2
NM_030962.4 missense, splice_region

Scores

2
17
Splicing: ADA: 0.8497
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 2.32
Variant links:
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-AS1 (HGNC:27438): (SBF2 antisense RNA 1)

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -7 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.096526414).
BS1
Variant frequency is greater than expected in population eas. gnomad4 allele frequency = 0.0000591 (9/152264) while in subpopulation EAS AF= 0.00116 (6/5190). AF 95% confidence interval is 0.000503. There are 0 homozygotes in gnomad4. There are 4 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High Homozygotes in GnomAdExome4 at 2 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SBF2NM_030962.4 linkc.5035C>T p.Arg1679Cys missense_variant, splice_region_variant Exon 36 of 40 ENST00000256190.13 NP_112224.1 Q86WG5-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SBF2ENST00000256190.13 linkc.5035C>T p.Arg1679Cys missense_variant, splice_region_variant Exon 36 of 40 1 NM_030962.4 ENSP00000256190.8 Q86WG5-1

Frequencies

GnomAD3 genomes
AF:
0.0000592
AC:
9
AN:
152146
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00115
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000199
AC:
5
AN:
251454
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135896
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000163
Gnomad SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.000142
AC:
208
AN:
1461448
Hom.:
2
Cov.:
30
AF XY:
0.000121
AC XY:
88
AN XY:
727030
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00516
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
9.00e-7
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000591
AC:
9
AN:
152264
Hom.:
0
Cov.:
32
AF XY:
0.0000537
AC XY:
4
AN XY:
74446
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00116
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00
ExAC
AF:
0.0000330
AC:
4
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Nov 05, 2019
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.R1679C variant (also known as c.5035C>T), located in coding exon 36 of the SBF2 gene, results from a C to T substitution at nucleotide position 5035. The arginine at codon 1679 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is poorly conserved in available vertebrate species. 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. -

Charcot-Marie-Tooth disease type 4B2 Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Charcot-Marie-Tooth disease type 4 Uncertain:1
Apr 29, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 1679 of the SBF2 protein (p.Arg1679Cys). This variant is present in population databases (rs79401259, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with SBF2-related conditions. ClinVar contains an entry for this variant (Variation ID: 71400). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). 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
0.083
BayesDel_addAF
Benign
-0.18
T
BayesDel_noAF
Benign
-0.28
CADD
Pathogenic
27
DANN
Benign
0.97
DEOGEN2
Benign
0.12
T;.
Eigen
Benign
0.085
Eigen_PC
Benign
0.17
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Benign
0.83
T;T
M_CAP
Benign
0.030
D
MetaRNN
Benign
0.097
T;T
MetaSVM
Benign
-0.60
T
MutationAssessor
Benign
0.69
N;.
PrimateAI
Benign
0.21
T
PROVEAN
Benign
-1.1
N;N
REVEL
Benign
0.26
Sift
Benign
0.037
D;D
Sift4G
Uncertain
0.019
D;D
Polyphen
0.72
P;.
Vest4
0.24
MVP
0.87
MPC
0.37
ClinPred
0.17
T
GERP RS
6.2
Varity_R
0.073
gMVP
0.37

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.85
dbscSNV1_RF
Benign
0.64
SpliceAI score (max)
0.010
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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs79401259; hg19: chr11-9809183; COSMIC: COSV56307368; COSMIC: COSV56307368; API