NM_017841.4:c.165G>A

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 16P and 4B. PVS1PP5_Very_StrongBS2

The NM_017841.4(SDHAF2):​c.165G>A​(p.Trp55*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,842 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

SDHAF2
NM_017841.4 stop_gained

Scores

5
1
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5U:1

Conservation

PhyloP100: 8.81

Publications

1 publications found
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]
SDHAF2 Gene-Disease associations (from GenCC):
  • hereditary pheochromocytoma-paraganglioma
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
  • pheochromocytoma/paraganglioma syndrome 2
    Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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.
PP5
Variant 11-61437753-G-A is Pathogenic according to our data. Variant chr11-61437753-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 384524.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS2
High AC in GnomAdExome4 at 7 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SDHAF2NM_017841.4 linkc.165G>A p.Trp55* stop_gained Exon 2 of 4 ENST00000301761.7 NP_060311.1 Q9NX18

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SDHAF2ENST00000301761.7 linkc.165G>A p.Trp55* stop_gained Exon 2 of 4 1 NM_017841.4 ENSP00000301761.3 Q9NX18
ENSG00000256591ENST00000541135.5 linkc.165G>A p.Trp55* stop_gained Exon 2 of 5 4 ENSP00000443130.1 F5H5T6

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.0000199
AC:
5
AN:
251250
AF XY:
0.0000295
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000440
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461842
Hom.:
0
Cov.:
32
AF XY:
0.00000688
AC XY:
5
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000630
AC:
7
AN:
1111972
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.482
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:5Uncertain:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hereditary pheochromocytoma-paraganglioma Pathogenic:3
Sep 18, 2023
All of Us Research Program, National Institutes of Health
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant changes 1 nucleotide in exon 2 of the SDHAF2 gene, creating a premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. This variant has not been reported in individuals affected with SDHAF2-like disorders, but a different variant with the same protein consequence (c.164G>A, p.Trp55*) has been observed in an individual with a bilateral carotid body tumor (PMID: 36597280). This variant has been identified in 5/251250 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Loss-of-function variants in SDHAF2 are an expected mechanism of disease (PMID: 22241717, 26096992). Based on the available evidence, this variant is classified as Pathogenic. -

Jun 22, 2023
Color Diagnostics, LLC DBA Color Health
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant changes 1 nucleotide in exon 2 of the SDHAF2 gene, creating a premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. This variant has not been reported in individuals affected with SDHAF2-like disorders, but a different variant with the same protein consequence (c.164G>A, p.Trp55*) has been observed in an individual with a bilateral carotid body tumor (PMID: 36597280). This variant has been identified in 5/251250 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Loss-of-function variants in SDHAF2 are an expected mechanism of disease (PMID: 22241717, 26096992). Based on the available evidence, this variant is classified as Pathogenic. -

Dec 26, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Trp55*) in the SDHAF2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in SDHAF2 are known to be pathogenic (PMID: 22241717, 26096992). This variant is present in population databases (rs774508076, gnomAD 0.004%). This variant has not been reported in the literature in individuals affected with SDHAF2-related conditions. ClinVar contains an entry for this variant (Variation ID: 384524). For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1
Nov 14, 2024
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 36597280, 31687641) -

Hereditary cancer-predisposing syndrome Pathogenic:1
Feb 03, 2023
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.W55* pathogenic mutation (also known as c.165G>A), located in coding exon 2 of the SDHAF2 gene, results from a G to A substitution at nucleotide position 165. This changes the amino acid from a tryptophan to a stop codon within coding exon 2. A similar variant resulting in the same protein truncation (c.164G>A, p.W55*) has been reported in a Japanese patient who was diagnosed with bilateral paragangliomas at age 73 (Yoshihama K et al. Clin Genet, 2023 Jan;:). This c.165G>A variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

not specified Uncertain:1
Apr 27, 2017
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:flagged submission
Collection Method:clinical testing

The p.Trp55X variant in SDHAF2 has not been previously reported in individuals w ith SDHAF2-associated hereditary paraganglioma-pheochromocytoma syndromes but ha s been identified in 3/66432 European chromosomes by the Exome Aggregation Conso rtium (ExAC, http://exac.broadinstitute.org; dbSNP rs774508076). This nonsense v ariant leads to a premature termination codon at position 55, which is predicted to lead to a truncated or absent protein. Although this variant is expected to severely impact the protein, the spectrum of disease-causing variants is not we ll defined for SDHAF2. In summary, the clinical significance of the p.Trp55X var iant is uncertain. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.53
D
BayesDel_noAF
Pathogenic
0.65
CADD
Pathogenic
39
DANN
Uncertain
1.0
Eigen
Pathogenic
1.2
Eigen_PC
Pathogenic
1.1
FATHMM_MKL
Pathogenic
1.0
D
PhyloP100
8.8
Vest4
0.81, 0.82, 0.77, 0.83
GERP RS
5.6
Mutation Taster
=2/198
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs774508076; hg19: chr11-61205225; API