chr11-5226928-A-G

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000518.5(HBB):​c.92+2T>C variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,106 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000027 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

HBB
NM_000518.5 splice_donor, intron

Scores

5
1
1
Splicing: ADA: 0.9953
1
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 8.02

Publications

17 publications found
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]
HBB Gene-Disease associations (from GenCC):
  • dominant beta-thalassemia
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), ClinGen
  • hemoglobin M disease
    Inheritance: AD Classification: DEFINITIVE, MODERATE, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, ClinGen
  • beta thalassemia
    Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
  • beta-thalassemia HBB/LCRB
    Inheritance: AR, SD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
  • sickle cell disease and related diseases
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • erythrocytosis, familial, 6
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • Heinz body anemia
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • sickle cell disease
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)
  • hereditary persistence of fetal hemoglobin-beta-thalassemia syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • beta-thalassemia intermedia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • beta-thalassemia major
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • delta-beta-thalassemia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hemoglobin C disease
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hemoglobin C-beta-thalassemia syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hemoglobin E disease
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hemoglobin E-beta-thalassemia syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hereditary persistence of fetal hemoglobin-sickle cell disease syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • sickle cell-beta-thalassemia disease syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • sickle cell-hemoglobin c disease syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • sickle cell-hemoglobin d disease syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • sickle cell-hemoglobin E disease syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease,
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 11-5226928-A-G is Pathogenic according to our data. Variant chr11-5226928-A-G is described in ClinVar as Pathogenic. ClinVar VariationId is 36334.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HBBNM_000518.5 linkc.92+2T>C splice_donor_variant, intron_variant Intron 1 of 2 ENST00000335295.4 NP_000509.1 P68871D9YZU5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HBBENST00000335295.4 linkc.92+2T>C splice_donor_variant, intron_variant Intron 1 of 2 1 NM_000518.5 ENSP00000333994.3 P68871

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152106
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251218
AF XY:
0.0000221
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:
0.0000352
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
Data not reliable, filtered out with message: AS_VQSR
AF:
0.00000274
AC:
4
AN:
1460306
Hom.:
0
Cov.:
33
AF XY:
0.00000275
AC XY:
2
AN XY:
726588
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33442
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86228
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53410
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5758
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1110602
Other (OTH)
AF:
0.00
AC:
0
AN:
60330
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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
AF:
0.00000657
AC:
1
AN:
152106
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74290
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41438
American (AMR)
AF:
0.00
AC:
0
AN:
15270
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67984
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:
0.00000747
Hom.:
0

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

beta Thalassemia Pathogenic:3
Mar 17, 2017
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Nov 25, 2019
The ITHANET community portal, The Cyprus Institute of Neurology and Genetics
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:curation

- -

Jul 08, 2021
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: HBB c.92+2T>C is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. The variant allele was found at a frequency of 1.6e-05 in 251218 control chromosomes. c.92+2T>C has been reported in the literature in multiple individuals affected with Beta Thalassemia (Gonzalez-Redondo_1989, Bouhass_1990, Agouti_2008, IbnAyub_2010). These data indicate that the variant is very likely to be associated with disease. Four clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:3
Aug 17, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. ClinVar contains an entry for this variant (Variation ID: 36334). Disruption of this splice site has been observed in individuals with beta thalassemia (PMID: 2200760, 24986053, 28366028, 28391758). This variant is present in population databases (rs33956879, gnomAD 0.004%). This sequence change affects a donor splice site in intron 1 of the HBB gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in HBB are known to be pathogenic (PMID: 23637309). -

Jun 14, 2017
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 24, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The HBB c.92+2T>C variant (rs33956879, HbVar ID: 820), also known as IVS-I-2 (T>C), has been reported in an individual with HbS/beta(0) thalassemia (Gonzalez-Redondo 1989), and an individual with beta-thalassemia major (Kluge 2014). It was found in-trans with another pathogenic variant in both reported cases (Gonzalez-Redondo 1989, Kluge 2014). The c.92+2T>C variant is reported as pathogenic in ClinVar (Variation ID: 36334), and found in the general population with a low overall allele frequency of 0.002% (4/245978 alleles) in the Genome Aggregation Database. This variant abolishes the canonical splice donor site of intron 1, which is likely to disrupt gene function. Based on available information, this variant is considered to be pathogenic. References: Link to HbVar database: https://globin.bx.psu.edu/hbvar/hbvar.html Gonzalez-Redondo J et al. Severe Hb S-beta zero-thalassaemia with a T----C substitution in the donor splice site of the first intron of the beta-globin gene. Br J Haematol. 1989; 71(1):113-7. PMID: 2917118 Kluge M et al. Beta-Thalassemia major resulting from compound heterozygosity for HBB: c.92+2T>C [formerly known as IVS-I-2 (T>C)] and a novel beta(0)-thalassemia frameshift mutation: HBB: c.209delG; p.Gly70Valfs*20. Hemoglobin. 2014; 38(4):292-4. PMID: 24986053 -

Beta zero thalassemia Pathogenic:1
Sep 01, 1990
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

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
Sep 10, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.60
D
BayesDel_noAF
Pathogenic
0.37
CADD
Pathogenic
32
DANN
Uncertain
0.99
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.96
FATHMM_MKL
Pathogenic
0.98
D
PhyloP100
8.0
GERP RS
5.2
PromoterAI
-0.041
Neutral
Mutation Taster
=0/100
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Benign
0.71
SpliceAI score (max)
0.95
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.43
Position offset: 18
DS_DL_spliceai
0.95
Position offset: 2

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

Publications

Other links and lift over

dbSNP: rs33956879; hg19: chr11-5248158; API