11-5226962-G-T

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 6P and 1B. PM1PM2PM5BP6

The NM_000518.5(HBB):​c.60C>A​(p.Asn20Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,784 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N20D) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

HBB
NM_000518.5 missense

Scores

5
13

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:1O:1

Conservation

PhyloP100: -3.90

Publications

6 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 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 5 benign, 39 uncertain in NM_000518.5
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr11-5226963-T-C is described in ClinVar as Pathogenic. ClinVar VariationId is 15258.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP6
Variant 11-5226962-G-T is Benign according to our data. Variant chr11-5226962-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 15153.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000518.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
HBB
NM_000518.5
MANE Select
c.60C>Ap.Asn20Lys
missense
Exon 1 of 3NP_000509.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
HBB
ENST00000335295.4
TSL:1 MANE Select
c.60C>Ap.Asn20Lys
missense
Exon 1 of 3ENSP00000333994.3
HBB
ENST00000485743.1
TSL:1
c.60C>Ap.Asn20Lys
missense
Exon 1 of 2ENSP00000496200.1
HBB
ENST00000647020.1
c.60C>Ap.Asn20Lys
missense
Exon 1 of 3ENSP00000494175.1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152118
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:
0.00633
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461548
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
727110
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33468
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5764
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111704
Other (OTH)
AF:
0.00
AC:
0
AN:
60386
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
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152236
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74456
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41554
American (AMR)
AF:
0.00
AC:
0
AN:
15296
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10608
Middle Eastern (MID)
AF:
0.00680
AC:
2
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67992
Other (OTH)
AF:
0.00
AC:
0
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:1Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:1
Mar 20, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: HBB c.60C>A (p.Asn20Lys, also known as Hb D Ouled Rabah) results in a non-conservative amino acid change located in the Globin domain (IPR000971) of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant was absent in 251238 control chromosomes in gnomAD v2. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.60C>A has been reported in the literature along with a VUS missense p.Glu23Gln in individuals affected with Beta Thalassemia (example, Elion_1973). These report(s) do not provide unequivocal conclusions about association of the variant with Beta Thalassemia. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Additionally, p.Asn20Ser has been evaluated associated with disease as a splice-site variant, however such indirect evidence cannot be used for c.60C>A, as consensus agreement among computation tools predict no significant impact on normal splicing of this variant. The following publication have been ascertained in the context of this evaluation (PMID: 4719147). ClinVar contains an entry for this variant (Variation ID: 15153). Based on the evidence outlined above, the variant was classified as uncertain significance.

not provided Benign:1
Apr 28, 2021
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

HEMOGLOBIN D (OULED RABAH) Other:1
Dec 12, 2017
OMIM
Significance:other
Review Status:no assertion criteria provided
Collection Method:literature only

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.15
BayesDel_addAF
Benign
-0.016
T
BayesDel_noAF
Benign
-0.26
CADD
Benign
0.0020
DANN
Benign
0.64
DEOGEN2
Benign
0.043
T
Eigen
Benign
-1.9
Eigen_PC
Benign
-2.1
FATHMM_MKL
Benign
0.15
N
LIST_S2
Benign
0.75
T
M_CAP
Uncertain
0.26
D
MetaRNN
Uncertain
0.62
D
MetaSVM
Benign
-0.64
T
MutationAssessor
Benign
0.70
N
PhyloP100
-3.9
PrimateAI
Uncertain
0.55
T
PROVEAN
Uncertain
-3.1
D
REVEL
Uncertain
0.47
Sift
Benign
0.099
T
Sift4G
Benign
0.21
T
Polyphen
0.035
B
Vest4
0.85
MutPred
0.76
Gain of methylation at N20 (P = 0.0224)
MVP
0.66
MPC
0.039
ClinPred
0.098
T
GERP RS
-11
PromoterAI
-0.025
Neutral
Varity_R
0.28
gMVP
0.52
Mutation Taster
=12/88
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
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: rs63750840; hg19: chr11-5248192; API