11-61437726-C-G

Variant names:

• chr11-61437726-C-G
• rs969049910
• NM_017841.4:c.138C>G

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_017841.4(SDHAF2):​c.138C>G​(p.Asp46Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,818 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D46N) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SDHAF2 NM_017841.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.166
• Publications: 0 publications found

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

ENSG00000256591 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.18717861).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SDHAF2	NM_017841.4	c.138C>G	p.Asp46Glu	missense_variant	Exon 2 of 4	ENST00000301761.7	NP_060311.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SDHAF2	ENST00000301761.7	c.138C>G	p.Asp46Glu	missense_variant	Exon 2 of 4	1	NM_017841.4	ENSP00000301761.3
ENSG00000256591	ENST00000541135.5	c.138C>G	p.Asp46Glu	missense_variant	Exon 2 of 5	4		ENSP00000443130.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461818 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727214

African (AFR) AF: 0.00 AC: 0 AN: 33480

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: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111942

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Apr 28, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.D46E variant (also known as c.138C>G), located in coding exon 2 of the SDHAF2 gene, results from a C to G substitution at nucleotide position 138. The aspartic acid at codon 46 is replaced by glutamic acid, an amino acid with highly similar properties. This amino acid position is conserved. 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. -

Hereditary pheochromocytoma-paraganglioma Uncertain:1

Jun 07, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has not been reported in the literature in individuals affected with SDHAF2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces aspartic acid, which is acidic and polar, with glutamic acid, which is acidic and polar, at codon 46 of the SDHAF2 protein (p.Asp46Glu). ClinVar contains an entry for this variant (Variation ID: 532523). 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. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.40
BayesDel_addAF	Uncertain	0.027	T
BayesDel_noAF	Benign	-0.20
CADD	Benign	17
DANN	Uncertain	1.0
DEOGEN2	Benign	0.040	.;T;.;.;.
Eigen	Benign	0.094
Eigen_PC	Benign	0.021
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Benign	0.83	T;T;T;T;T
M_CAP	Uncertain	0.10	D
MetaRNN	Benign	0.19	T;T;T;T;T
MetaSVM	Benign	-0.34	T
MutationAssessor	Uncertain	2.3	.;M;.;.;.
PhyloP100		0.17
PrimateAI	Uncertain	0.64	T
PROVEAN	Benign	-1.4	N;N;.;.;N
REVEL	Uncertain	0.36
Sift	Uncertain	0.0060	D;D;.;.;D
Sift4G	Benign	0.096	T;T;T;T;T
Polyphen		0.98	.;D;.;.;.
Vest4		0.61, 0.56, 0.60, 0.62
MutPred		0.19		Loss of loop (P = 0.0804);Loss of loop (P = 0.0804);Loss of loop (P = 0.0804);Loss of loop (P = 0.0804);Loss of loop (P = 0.0804);
MVP		0.45
MPC		0.57
ClinPred		0.81	D
GERP RS		2.9
Varity_R		0.14
gMVP		0.27
Mutation Taster		=77/23	polymorphism

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

dbSNP: rs969049910; hg19: chr11-61205198;