rs34793594

chr11-5225734-A-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_000518.5(HBB):c.316-8T>G variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: HBB NM_000518.5 splice_region, splice_polypyrimidine_tract, intron
• Scores: Splicing: ADA: 0.00005425
• Clinical Significance: Likely benign criteria provided, single submitter P:2 B:1
• Conservation: PhyloP100: 0.623

Genes affected

HBB (HGNC:4827): (hemoglobin subunit beta) The alpha (HBA) and beta (HBB) loci determine the structure of the 2 types of polypeptide chains in adult hemoglobin, Hb A. The normal adult hemoglobin tetramer consists of two alpha chains and two beta chains. Mutant beta globin causes sickle cell anemia. Absence of beta chain causes beta-zero-thalassemia. Reduced amounts of detectable beta globin causes beta-plus-thalassemia. The order of the genes in the beta-globin cluster is 5'-epsilon -- gamma-G -- gamma-A -- delta -- beta--3'. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.8).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HBB	NM_000518.5	c.316-8T>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000335295.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HBB	ENST00000335295.4	c.316-8T>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_000518.5	P1
HBB	ENST00000647020.1	c.316-8T>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant				P1
HBB	ENST00000633227.1	c.*132-8T>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant, NMD_transcript_variant		3
HBB	ENST00000475226.1	n.248-8T>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant, non_coding_transcript_variant		2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely benign

Submissions summary: Pathogenic:2 Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

beta Thalassemia Pathogenic:1

Pathogenic, no assertion criteria provided

curation

The ITHANET community portal, The Cyprus Institute of Neurology and Genetics

Nov 25, 2019

- -

Beta-plus-thalassemia Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Jun 10, 1988

- -

not provided Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jun 23, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
Cadd	Benign	4.2
Dann	Benign	0.73

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000054
dbscSNV1_RF	Benign	0.012
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: rs34793594; hg19: chr11-5246964;