rs569245129

chr1-17053945-C-Gchr1-17053945-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_003000.3(SDHB):c.72+3G>C variant causes a splice donor region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,459,216 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 (★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: SDHB NM_003000.3 splice_donor_region, intron
• Scores: Splicing: ADA: 0.01358
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.415

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.44).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SDHB	NM_003000.3	c.72+3G>C		splice_donor_region_variant, intron_variant		ENST00000375499.8
SDHB	NM_001407361.1	c.72+3G>C		splice_donor_region_variant, intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SDHB	ENST00000375499.8	c.72+3G>C		splice_donor_region_variant, intron_variant		1	NM_003000.3	P1
SDHB	ENST00000466613.2	n.84+3G>C		splice_donor_region_variant, intron_variant, non_coding_transcript_variant		2
SDHB	ENST00000485515.5	n.60+3G>C		splice_donor_region_variant, intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000412 AC: 1 AN: 242444 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 131862

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000551

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459216 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 725918

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Pheochromocytoma;C0238198:Gastrointestinal stromal tumor;C1861848:Paragangliomas 4 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 14, 2023

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. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. This variant has not been reported in the literature in individuals affected with SDHB-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change falls in intron 1 of the SDHB gene. It does not directly change the encoded amino acid sequence of the SDHB protein. It affects a nucleotide within the consensus splice site. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.44
Cadd	Benign	13
Dann	Benign	0.84
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		3.1

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.014
dbscSNV1_RF	Benign	0.17
SpliceAI score (max)		0.020		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

Other links and lift over

dbSNP: rs569245129; hg19: chr1-17380440;