rs786204138

Positions:

• chr11-9845565-C-G
• chr11-9845565-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_030962.4(SBF2):​c.3110G>C​(p.Arg1037Pro) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.000000685 in 1,460,590 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SBF2 NM_030962.4 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.83

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]

(HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SBF2	NM_030962.4	c.3110G>C	p.Arg1037Pro	missense_variant, splice_region_variant	24/40	ENST00000256190.13	NP_112224.1
LOC101928008	NR_120539.1	n.135+6289C>G		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SBF2	ENST00000256190.13	c.3110G>C	p.Arg1037Pro	missense_variant, splice_region_variant	24/40	1	NM_030962.4	ENSP00000256190	P3
	ENST00000533659.1	n.134+6289C>G		intron_variant, non_coding_transcript_variant		1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460590 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 726676

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 26, 2016

In summary, this is a novel missense change at the end of the exon with uncertain impact on protein function and splicing. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of this changes on mRNA splicing suggest that this sequence change may alter mRNA splicing, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a SBF2-related disease ClinVar contains an entry for this variant (Variation ID: 188198). This sequence change replaces arginine with proline at codon 1037 of the SBF2 protein (p.Arg1037Pro). The arginine residue is moderately conserved and there is a moderate physicochemical difference between arginine and proline. It also falls at the last nucleotide of exon 24 of the SBF2 mRNA. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.65	D
Eigen	Pathogenic	0.75
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.97	D
M_CAP	Uncertain	0.25	D
MetaRNN	Pathogenic	0.86	D
MetaSVM	Uncertain	0.35	D
MutationAssessor	Benign	1.9	L
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.78	T
PROVEAN	Pathogenic	-4.4	D
REVEL	Pathogenic	0.67
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0050	D
Polyphen		1.0	D
Vest4		0.91
MutPred		0.40		Loss of MoRF binding (P = 0.002);
MVP		0.99
MPC		0.68
ClinPred		1.0	D
GERP RS		6.0
Varity_R		0.68
gMVP		0.69

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.99
SpliceAI score (max)		0.40		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.40		Position offset: 0

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

Publications

LitVar

Other links and lift over

dbSNP: rs748477865; hg19: chr11-9867112;