rs33935383

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1PM2PP3

The NM_000518.5(HBB):​c.371C>T​(p.Thr124Ile) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,738 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 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. T124N) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

HBB
NM_000518.5 missense

Scores

7
6
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3O:1

Conservation

PhyloP100: 4.18

Publications

5 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: Uncertain_significance. The variant received 5 ACMG points.

PM1
In a hotspot region, there are 13 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 37 uncertain in NM_000518.5
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.837

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HBBNM_000518.5 linkc.371C>T p.Thr124Ile missense_variant Exon 3 of 3 ENST00000335295.4 NP_000509.1 P68871D9YZU5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HBBENST00000335295.4 linkc.371C>T p.Thr124Ile missense_variant Exon 3 of 3 1 NM_000518.5 ENSP00000333994.3 P68871

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251294
AF XY:
0.00000736
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:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461738
Hom.:
0
Cov.:
31
AF XY:
0.00000275
AC XY:
2
AN XY:
727190
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111886
Other (OTH)
AF:
0.00
AC:
0
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
33
Alfa
AF:
0.00
Hom.:
0
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Dec 19, 2016
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

beta Thalassemia Uncertain:1
Sep 16, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Uncertain:1
Mar 18, 2023
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The HBB c.371C>T (p.Thr124Ile) variant (also known as Hb Villejuif) is described as an asymptomatic variant in heterozygous carriers with normal stability. This silent variant was first reported in an individual who coincidentally had polycythemia vera with the red blood cells showing normal oxygen binding properties (PMID: 2816924 (1989)). Later, the variant was observed in a family who had normal hemoglobin analysis results with a slight increase in Hb A2 concentration (PMID: 11300351 (2001)). Based on the available information, we are unable to determine the clinical significance of this variant. -

HEMOGLOBIN VILLEJUIF Other:1
Dec 12, 2017
OMIM
Significance:other
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.53
BayesDel_addAF
Pathogenic
0.47
D
BayesDel_noAF
Pathogenic
0.44
CADD
Benign
20
DANN
Benign
0.95
DEOGEN2
Benign
0.41
T;T
Eigen
Benign
-0.058
Eigen_PC
Benign
-0.15
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Benign
0.82
.;T
M_CAP
Pathogenic
0.40
D
MetaRNN
Pathogenic
0.84
D;D
MetaSVM
Uncertain
0.70
D
MutationAssessor
Pathogenic
4.0
H;H
PhyloP100
4.2
PrimateAI
Uncertain
0.55
T
PROVEAN
Uncertain
-3.9
D;.
REVEL
Pathogenic
0.65
Sift
Pathogenic
0.0
D;.
Sift4G
Uncertain
0.037
D;.
Polyphen
0.72
P;P
Vest4
0.89
MutPred
0.57
Loss of disorder (P = 0.0411);Loss of disorder (P = 0.0411);
MVP
0.98
MPC
0.039
ClinPred
0.55
D
GERP RS
2.8
Varity_R
0.30
gMVP
0.89
Mutation Taster
=35/65
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
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: rs33935383; hg19: chr11-5246901; API