11-5226947-A-T

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM2PP5_Very_Strong

The NM_000518.5(HBB):​c.75T>A​(p.Gly25Gly) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000744 in 1,613,626 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

HBB
NM_000518.5 synonymous

Scores

2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:9O:1

Conservation

PhyloP100: -0.744
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 10 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 11-5226947-A-T is Pathogenic according to our data. Variant chr11-5226947-A-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 15459.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr11-5226947-A-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
HBBNM_000518.5 linkuse as main transcriptc.75T>A p.Gly25Gly synonymous_variant 1/3 ENST00000335295.4 NP_000509.1 P68871D9YZU5

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
HBBENST00000335295.4 linkuse as main transcriptc.75T>A p.Gly25Gly synonymous_variant 1/31 NM_000518.5 ENSP00000333994.3 P68871

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152160
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000193
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
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
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251294
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135812
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
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:
0.00000274
AC:
4
AN:
1461466
Hom.:
0
Cov.:
33
AF XY:
0.00000138
AC XY:
1
AN XY:
727084
show subpopulations
Gnomad4 AFR exome
AF:
0.0000896
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
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
AF:
0.0000526
AC:
8
AN:
152160
Hom.:
0
Cov.:
32
AF XY:
0.0000404
AC XY:
3
AN XY:
74330
show subpopulations
Gnomad4 AFR
AF:
0.000193
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.000110

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:9Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:4
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpNov 05, 2023This sequence change affects codon 25 of the HBB mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the HBB protein. This variant is present in population databases (rs33951465, gnomAD 0.02%). This variant has been observed in individual(s) with beta thalassaemia (PMID: 2458145, 2634667, 28366028). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 15459). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingARUP Laboratories, Molecular Genetics and Genomics, ARUP LaboratoriesNov 28, 2023The HBB c.75T>A; p.Gly25Gly variant (also known as Gly24Gly when numbered from the mature protein or as codon 24 (T>A), rs33951465, HbVar ID: 805) has been reported in individuals with beta thalassemia who were homozygous for the variant or compound heterozygous with another pathogenic variant (see HbVar and ClinVar links, Gonzalez-Redondo 1988, Hattori 1989). This synonymous variant introduces a cryptic acceptor splice site and has been shown to alter splicing by reducing normal beta globin transcripts by about 75 percent (Goldsmith 1983). Based on available information, this variant is considered to be pathogenic. References: Link to HbVar database: https://globin.bx.psu.edu/hbvar/hbvar.html Goldsmith ME et al. "Silent" nucleotide substitution in a beta+-thalassemia globin gene activates splice site in coding sequence RNA. Proc Natl Acad Sci U S A. 1983; 80(8):2318-22. PMID: 6572978 Gonzalez-Redondo JM et al. Clinical and genetic heterogeneity in black patients with homozygous beta-thalassemia from the southeastern United States. Blood. 1988; 72(3):1007-14. PMID: 2458145 Hattori Y et al. Characterization of beta-thalassemia mutations among the Japanese. Hemoglobin. 1989; 13(7-8):657-70. PMID: 2634667 -
Pathogenic, criteria provided, single submitterclinical testingQuest Diagnostics Nichols Institute San Juan CapistranoJun 03, 2024The HBB c.75T>A (p.Gly25=) synonymous variant has been reported in the published literature in several individuals affected with beta(+) thalassemia (PMIDs: 2458145 (1988), 2634667 (1989), 20737602 (2010), 23590658 (2013), 28366028 (2017), 29669226 (2018), 31788855 (2020), 36106931 (2022)). This variant is reported to activate a cryptic splice donor site and significantly reduce the amount of normal HBB mRNA produced (PMID: 6572978 (1983)). The frequency of this variant in the general population, 0.0002 (5/24970 chromosomes (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is consistent with pathogenicity. Based on the available information, this variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingGeneDxNov 18, 2024Published functional studies demonstrate abnormal splicing and a decrease of normally processed beta-globin mRNA (PMID: 6572978); In silico analysis supports a deleterious effect on splicing; Also known as Gly24Gly; This variant is associated with the following publications: (PMID: 25087612, 22975760, 29669226, 26044735, 2458145, 2634667, 23590658, 28366028, 6572978) -
beta Thalassemia Pathogenic:2Other:1
not provided, no classification providedliterature onlyGeneReviews-- -
Likely pathogenic, criteria provided, single submitterclinical testingMyriad Genetics, Inc.Dec 20, 2019NM_000518.4(HBB):c.75T>A(aka G25=) is classified as likely pathogenic in the context of Hb beta chain-related hemoglobinopathy and is associated with beta thalassemia. Sources cited for classification include the following: PMID 2458145, 6572978, 6583702 and 23590658. Classification of NM_000518.4(HBB):c.75T>A(aka G25=) is based on the following criteria: This variant has been observed more frequently in patients with clinical diagnoses than in healthy populations. Please note: this variant was assessed in the context of healthy population screening. -
Pathogenic, criteria provided, single submitterclinical testing;curationWomen's Health and Genetics/Laboratory Corporation of America, LabCorpAug 18, 2011- -
alpha Thalassemia;C0002895:Hb SS disease;C0019025:Hereditary persistence of fetal hemoglobin;C0700299:Heinz body anemia;C1840779:METHEMOGLOBINEMIA, BETA TYPE;C1858990:Dominant beta-thalassemia;C1970028:Malaria, susceptibility to;C4693822:Erythrocytosis, familial, 6;CN322236:Beta-thalassemia HBB/LCRB Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsSep 16, 2021- -
Hb SS disease Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingBaylor Genetics-- -
Beta-plus-thalassemia Pathogenic:1
Pathogenic, no assertion criteria providedliterature onlyOMIMApr 01, 1983- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.50
CADD
Benign
20
DANN
Benign
0.81

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.80
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.80
Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs33951465; hg19: chr11-5248177; API