chr11-66056952-C-T

Variant names:

• chr11-66056952-C-T
• NM_006842.3:c.664C>T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_006842.3(SF3B2):​c.664C>T​(p.Arg222*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,456,452 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SF3B2 NM_006842.3 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.53
• Publications: 0 publications found

Genes affected

SF3B2 (HGNC:10769): (splicing factor 3b subunit 2) This gene encodes subunit 2 of the splicing factor 3b protein complex. Splicing factor 3b, together with splicing factor 3a and a 12S RNA unit, forms the U2 small nuclear ribonucleoproteins complex (U2 snRNP). The splicing factor 3b/3a complex binds pre-mRNA upstream of the intron's branch site in a sequence-independent manner and may anchor the U2 snRNP to the pre-mRNA. Splicing factor 3b is also a component of the minor U12-type spliceosome. Subunit 2 associates with pre-mRNA upstream of the branch site at the anchoring site. Subunit 2 also interacts directly with subunit 4 of the splicing factor 3b complex. Subunit 2 is a highly hydrophilic protein with a proline-rich N-terminus and a glutamate-rich stretch in the C-terminus. [provided by RefSeq, Jul 2008]

ENSG00000255038 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-66056952-C-T is Pathogenic according to our data. Variant chr11-66056952-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 3254890.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SF3B2	NM_006842.3	c.664C>T	p.Arg222*	stop_gained	Exon 6 of 22	ENST00000322535.11	NP_006833.2
SF3B2	XM_005273726.5	c.664C>T	p.Arg222*	stop_gained	Exon 6 of 22		XP_005273783.1
SF3B2	XM_011544740.4	c.661C>T	p.Arg221*	stop_gained	Exon 6 of 22		XP_011543042.1
SF3B2	XM_017017144.3	c.661C>T	p.Arg221*	stop_gained	Exon 6 of 22		XP_016872633.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SF3B2	ENST00000322535.11	c.664C>T	p.Arg222*	stop_gained	Exon 6 of 22	1	NM_006842.3	ENSP00000318861.6

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1456452 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 724846

⚠️ 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: 33368

American (AMR) AF: 0.00 AC: 0 AN: 44716

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26098

East Asian (EAS) AF: 0.00 AC: 0 AN: 39658

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86146

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53402

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 9.03e-7 AC: 1 AN: 1107064

Other (OTH) AF: 0.00 AC: 0 AN: 60238

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.006664), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Craniofacial microsomia 1 Pathogenic:1

Jul 17, 2023

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with craniofacial microsomia (MIM#164210). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0115 - Variants in this gene are known to have variable expressivity, with intrafamilial variability well reported (PMID: 34344887). (I) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0702 - Other NMD-predicted variants comparable to the one identified in this case have strong previous evidence for pathogenicity. These variants have been reported as pathogenic, and observed in at least five individuals with craniofacial microsomia (ClinVar, PMID: 34344887). (SP) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	38
DANN	Uncertain	1.0
Eigen	Uncertain	0.48
Eigen_PC	Uncertain	0.33
FATHMM_MKL	Uncertain	0.96	D
PhyloP100		2.5
Vest4		0.42
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8
Mutation Taster		=5/195	disease causing (fs/PTC)

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

hg19: chr11-65824423;