rs1456129845

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 5P and 4B. PVS1_StrongPP5BS2

The ENST00000301761.7(SDHAF2):​c.355dup​(p.Tyr119LeufsTer8) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000868 in 1,612,996 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. I118I) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

SDHAF2
ENST00000301761.7 frameshift

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5U:2

Conservation

PhyloP100: 7.27
Variant links:
Genes affected
SDHAF2 (HGNC:26034): (succinate dehydrogenase complex assembly factor 2) This gene encodes a mitochondrial assembly factor needed for the flavination of a succinate dehydrogenase complex subunit (SDHA), which is required for activity of the succinate dehydrogenase complex. Mutations in this gene are associated with paraganglioma. [provided by RefSeq, May 2022]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.297 CDS is truncated, and there are 3 pathogenic variants in the truncated region.
PP5
Variant 11-61438095-A-AT is Pathogenic according to our data. Variant chr11-61438095-A-AT is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 403423.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Pathogenic=1, Uncertain_significance=2}.
BS2
High AC in GnomAdExome4 at 10 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
SDHAF2NM_017841.4 linkuse as main transcriptc.355dup p.Tyr119LeufsTer8 frameshift_variant 3/4 ENST00000301761.7 NP_060311.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
SDHAF2ENST00000301761.7 linkuse as main transcriptc.355dup p.Tyr119LeufsTer8 frameshift_variant 3/41 NM_017841.4 ENSP00000301761 P1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152082
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251486
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135918
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000685
AC:
10
AN:
1460914
Hom.:
0
Cov.:
33
AF XY:
0.00000275
AC XY:
2
AN XY:
726842
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000900
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152082
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74286
show subpopulations
Gnomad4 AFR
AF:
0.0000483
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:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000868
Hom.:
0
Bravo
AF:
0.0000189

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:5Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Hereditary pheochromocytoma-paraganglioma Pathogenic:1Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpOct 20, 2023This sequence change creates a premature translational stop signal (p.Tyr119Leufs*8) in the SDHAF2 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 48 amino acid(s) of the SDHAF2 protein. This variant is present in population databases (no rsID available, gnomAD 0.004%). This premature translational stop signal has been observed in individual(s) with a right carotid body paranglioma (PMID: 22241717). ClinVar contains an entry for this variant (Variation ID: 403423). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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. -
Likely pathogenic, criteria provided, single submitterclinical testingAll of Us Research Program, National Institutes of HealthSep 23, 2024This variant inserts 1 nucleotide in exon 3 of the SDHAF2 gene, creating a frameshift and premature translation stop signal. This variant is expected to escape nonsense-mediated decay but result in a non-functional protein product. This variant impacts the C-terminal 48 amino acids. Functional studies have shown that a deletion of the C-terminal 15 amino acids of SDHAF2 abolished SDHA-SDHAF2 interaction and SDHA flavination (PMID: 32887801). This variant has been reported in an individual affected with a right carotid body paraganglioma (PMID: 22241717). This variant has been identified in 2/282866 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Based on the available evidence, this variant is classified as Likely Pathogenic. -
Paragangliomas 2 Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsJun 13, 2023- -
SDHAF2-related disorder Pathogenic:1
Likely pathogenic, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesJan 29, 2024The SDHAF2 c.355dupT variant is predicted to result in a frameshift and premature protein termination (p.Tyr119Leufs*8). This variant has been reported in patients with paraganglioma/pheochromocytoma tumors (Table S1 in Evenepoel L et al 2014. PubMed ID: 25394176; reported as c.357_358insT Piccini et al. 2012. PubMed ID: 22241717). This variant occurs in the 2nd to last exon and may not result in non-sense mediated decay. This variant is reported in 0.0040% of alleles in individuals of African descent in gnomAD. Frameshift variants in SDHAF2 are expected to be pathogenic. This variant is interpreted as likely pathogenic. -
not provided Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenJul 01, 2024SDHAF2: PVS1:Strong, PM2, PS4:Moderate -
Hereditary cancer-predisposing syndrome Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingAmbry GeneticsJun 11, 2024The c.355dupT (p.Y119Lfs*8) alteration, located in exon 3 (coding exon 3) of the SDHAF2 gene, consists of a duplication of T at position 355, causing a translational frameshift with a predicted alternate stop codon after 8 amino acids. This alteration occurs at the 3' terminus of theSDHAF2 gene, is not expected to trigger nonsense-mediated mRNA decay, and impacts the last 48 amino acids of the protein. However, premature stop codons are typically deleterious in nature and a significant portion of the protein is affected (Ambry internal data). Based on data from gnomAD, this allele has an overall frequency of 0.001% (2/282866) total alleles studied. The highest observed frequency was 0.004% (1/24968) of African alleles. This variant (reported as c.357_358insT in one study) has been detected in two unrelated individuals with a paraganglioma (Piccini, 2012; Evenepoel, 2015). Based on internal structural analysis, this mutation removes a large portion of the SDHAF2-SDHA interface and is likely to disrupt protein function and stability (Hao, 2009; Eletsky, 2012; Sharma, 2020). Based on the available evidence, this alteration is classified as pathogenic. -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineJun 23, 2016Variant identified in a genome or exome case(s) and assessed due to predicted null impact of the variant or pathogenic assertions in the literature or databases. Disclaimer: This variant has not undergone full assessment. The following are preliminary notes: LOF not established disease mechanism for this gene -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.070
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: rs1456129845; hg19: chr11-61205567; API