rs1555186817

Variant summary

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

The NM_003002.4(SDHD):​c.167A>C​(p.His56Pro) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000125 in 1,595,314 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predict no significant impact on normal splicing. 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. H56R) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

SDHD
NM_003002.4 missense, splice_region

Scores

2
6
11
Splicing: ADA: 0.005218
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 0.738

Publications

0 publications found
Variant links:
Genes affected
SDHD (HGNC:10683): (succinate dehydrogenase complex subunit D) This gene encodes a member of complex II of the respiratory chain, which is responsible for the oxidation of succinate. The encoded protein is one of two integral membrane proteins anchoring the complex to the matrix side of the mitochondrial inner membrane. Mutations in this gene are associated with the formation of tumors, including hereditary paraganglioma. Transmission of disease occurs almost exclusively through the paternal allele, suggesting that this locus may be maternally imprinted. There are pseudogenes for this gene on chromosomes 1, 2, 3, 7, and 18. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2013]
SDHD Gene-Disease associations (from GenCC):
  • hereditary pheochromocytoma-paraganglioma
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • pheochromocytoma
    Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
  • pheochromocytoma/paraganglioma syndrome 1
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
  • Carney-Stratakis syndrome
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet
  • mitochondrial complex II deficiency, nuclear type 1
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • renal cell carcinoma
    Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
  • mitochondrial complex 2 deficiency, nuclear type 3
    Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics
  • mitochondrial complex II deficiency
    Inheritance: AR Classification: MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet
  • Cowden disease
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • intestinal cancer
    Inheritance: AD Classification: LIMITED Submitted by: G2P
  • mitochondrial disease
    Inheritance: AR Classification: LIMITED Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SDHDNM_003002.4 linkc.167A>C p.His56Pro missense_variant, splice_region_variant Exon 2 of 4 ENST00000375549.8 NP_002993.1 O14521-1A0A0S2Z4J3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SDHDENST00000375549.8 linkc.167A>C p.His56Pro missense_variant, splice_region_variant Exon 2 of 4 1 NM_003002.4 ENSP00000364699.3 O14521-1
ENSG00000255292ENST00000532699.1 linkn.167A>C splice_region_variant, non_coding_transcript_exon_variant Exon 2 of 6 3 ENSP00000456434.1 H3BRW5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152126
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
6.93e-7
AC:
1
AN:
1443188
Hom.:
0
Cov.:
26
AF XY:
0.00
AC XY:
0
AN XY:
719266
show subpopulations
⚠️ 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:
33120
American (AMR)
AF:
0.00
AC:
0
AN:
44698
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26014
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39610
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85948
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53342
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5746
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1094886
Other (OTH)
AF:
0.00
AC:
0
AN:
59824
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
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
AF:
0.00000657
AC:
1
AN:
152126
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74322
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41412
American (AMR)
AF:
0.00
AC:
0
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Pheochromocytoma;C1847319:Carney-Stratakis syndrome;C1868633:Paragangliomas with sensorineural hearing loss;CN166604:Cowden syndrome 3 Uncertain:1
Mar 07, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces histidine, which is basic and polar, with proline, which is neutral and non-polar, at codon 56 of the SDHD protein (p.His56Pro). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with SDHD-related conditions. ClinVar contains an entry for this variant (Variation ID: 465223). 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. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1
Jul 26, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.H56P variant (also known as c.167A>C), located in coding exon 2 of the SDHD gene, results from an A to C substitution at nucleotide position 167. The histidine at codon 56 is replaced by proline, 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
0.077
BayesDel_addAF
Pathogenic
0.23
D
BayesDel_noAF
Uncertain
0.10
CADD
Benign
17
DANN
Benign
0.94
DEOGEN2
Uncertain
0.69
D;.;.;.;.;.
Eigen
Benign
-0.30
Eigen_PC
Benign
-0.48
FATHMM_MKL
Benign
0.13
N
LIST_S2
Benign
0.76
T;T;T;T;T;.
M_CAP
Pathogenic
0.34
D
MetaRNN
Uncertain
0.43
T;T;T;D;T;T
MetaSVM
Uncertain
0.56
D
MutationAssessor
Benign
1.2
L;L;.;L;.;L
PhyloP100
0.74
PrimateAI
Benign
0.36
T
PROVEAN
Benign
-0.62
N;.;N;D;N;N
REVEL
Uncertain
0.59
Sift
Benign
0.058
T;.;D;D;D;D
Sift4G
Uncertain
0.045
D;D;T;D;T;D
Polyphen
0.92
P;.;.;.;.;.
Vest4
0.41
MutPred
0.43
Gain of relative solvent accessibility (P = 0.0166);Gain of relative solvent accessibility (P = 0.0166);Gain of relative solvent accessibility (P = 0.0166);Gain of relative solvent accessibility (P = 0.0166);Gain of relative solvent accessibility (P = 0.0166);Gain of relative solvent accessibility (P = 0.0166);
MVP
0.95
MPC
0.66
ClinPred
0.41
T
GERP RS
2.4
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.093
gMVP
0.72
Mutation Taster
=80/20
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.0052
dbscSNV1_RF
Benign
0.13
SpliceAI score (max)
0.11
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: rs1555186817; hg19: chr11-111958695; API