1-17044855-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 4P and 2B. PM1PM2BP4_Moderate

The NM_003000.3(SDHB):​c.106G>A​(p.Ala36Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,746 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 variant affecting the same amino acid position, but resulting in a different missense (i.e. A36I) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

SDHB
NM_003000.3 missense

Scores

6
13

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.12

Publications

0 publications found
Variant links:
Genes affected
SDHB (HGNC:10681): (succinate dehydrogenase complex iron sulfur subunit B) This tumor suppressor gene encodes the iron-sulfur protein subunit of the succinate dehydrogenase (SDH) enzyme complex which plays a critical role in mitochondria. The SDH enzyme complex is composed of four nuclear-encoded subunits. This enzyme complex converts succinate to fumarate which releases electrons as part of the citric acid cycle, and the enzyme complex additionally provides an attachment site for released electrons to be transferred to the oxidative phosphorylation pathway. The SDH enzyme complex plays a role in oxygen-related gene regulation through its conversion of succinate, which is an oxygen sensor that stabilizes the hypoxia-inducible factor 1 (HIF1) transcription factor. Sporadic and familial mutations in this gene result in paragangliomas, pheochromocytoma, and gastrointestinal stromal tumors, supporting a link between mitochondrial dysfunction and tumorigenesis. Mutations in this gene are also implicated in nuclear type 4 mitochondrial complex II deficiency. [provided by RefSeq, Jun 2022]
SDHB Gene-Disease associations (from GenCC):
  • Carney-Stratakis syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, G2P, Orphanet
  • gastrointestinal stromal tumor
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae)
  • hereditary pheochromocytoma-paraganglioma
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • pheochromocytoma
    Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
  • pheochromocytoma/paraganglioma syndrome 4
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • mitochondrial disease
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • renal cell carcinoma
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • mitochondrial complex 2 deficiency, nuclear type 4
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • Cowden disease
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • mitochondrial complex II deficiency
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 14 uncertain in NM_003000.3
PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.24506593).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SDHBNM_003000.3 linkc.106G>A p.Ala36Thr missense_variant Exon 2 of 8 ENST00000375499.8 NP_002991.2 P21912
SDHBNM_001407361.1 linkc.106G>A p.Ala36Thr missense_variant Exon 2 of 8 NP_001394290.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SDHBENST00000375499.8 linkc.106G>A p.Ala36Thr missense_variant Exon 2 of 8 1 NM_003000.3 ENSP00000364649.3 P21912

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251240
AF XY:
0.00000736
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:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000342
AC:
5
AN:
1461746
Hom.:
0
Cov.:
32
AF XY:
0.00000413
AC XY:
3
AN XY:
727172
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:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53334
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1111958
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.455
Heterozygous variant carriers
0
1
1
2
2
3
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

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1
May 12, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.A36T variant (also known as c.106G>A), located in coding exon 2 of the SDHB gene, results from a G to A substitution at nucleotide position 106. The alanine at codon 36 is replaced by threonine, an amino acid with similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.070
BayesDel_addAF
Uncertain
0.088
D
BayesDel_noAF
Benign
-0.11
CADD
Benign
15
DANN
Uncertain
0.99
DEOGEN2
Benign
0.32
T;.
Eigen
Benign
-0.36
Eigen_PC
Benign
-0.18
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Benign
0.75
T;T
M_CAP
Uncertain
0.18
D
MetaRNN
Benign
0.25
T;T
MetaSVM
Uncertain
0.59
D
MutationAssessor
Benign
1.3
L;.
PhyloP100
2.1
PrimateAI
Benign
0.48
T
PROVEAN
Benign
-0.87
N;.
REVEL
Uncertain
0.41
Sift
Benign
0.14
T;.
Sift4G
Benign
0.14
T;T
Polyphen
0.0
B;.
Vest4
0.24
MutPred
0.36
Loss of helix (P = 0.0093);.;
MVP
0.88
MPC
0.16
ClinPred
0.28
T
GERP RS
4.7
PromoterAI
0.0058
Neutral
Varity_R
0.033
gMVP
0.44
Mutation Taster
=84/16
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

Publications

Other links and lift over

dbSNP: rs1204932232; hg19: chr1-17371350; API