rs281864900

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000518.5(HBB):​c.126_129del​(p.Phe42LeufsTer19) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000923 in 1,614,116 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (β˜…β˜…).

Frequency

Genomes: 𝑓 0.000099 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000092 ( 0 hom. )

Consequence

HBB
NM_000518.5 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:22O:1

Conservation

PhyloP100: 8.66
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 18 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. There are 109 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 11-5226762-CAAAG-C is Pathogenic according to our data. Variant chr11-5226762-CAAAG-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 15417.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr11-5226762-CAAAG-C 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.126_129del p.Phe42LeufsTer19 frameshift_variant 2/3 ENST00000335295.4 NP_000509.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
HBBENST00000335295.4 linkuse as main transcriptc.126_129del p.Phe42LeufsTer19 frameshift_variant 2/31 NM_000518.5 ENSP00000333994 P1

Frequencies

GnomAD3 genomes
AF:
0.000105
AC:
16
AN:
152122
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00231
Gnomad SAS
AF:
0.000829
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000278
AC:
70
AN:
251398
Hom.:
0
AF XY:
0.000339
AC XY:
46
AN XY:
135860
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00234
Gnomad SAS exome
AF:
0.000882
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000917
AC:
134
AN:
1461876
Hom.:
0
AF XY:
0.000117
AC XY:
85
AN XY:
727246
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00108
Gnomad4 SAS exome
AF:
0.000962
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.000132
GnomAD4 genome
AF:
0.0000985
AC:
15
AN:
152240
Hom.:
0
Cov.:
32
AF XY:
0.000107
AC XY:
8
AN XY:
74450
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00212
Gnomad4 SAS
AF:
0.000829
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000113
Hom.:
0
Bravo
AF:
0.0000831

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:22Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:7
Pathogenic, criteria provided, single submitterclinical testingQuest Diagnostics Nichols Institute San Juan CapistranoNov 04, 2016- -
Pathogenic, criteria provided, single submitterclinical testingCenter for Pediatric Genomic Medicine, Children's Mercy Hospital and ClinicsMar 22, 2017- -
Pathogenic, criteria provided, single submitterclinical testingARUP Laboratories, Molecular Genetics and Genomics, ARUP LaboratoriesNov 21, 2023The HBB c.126_129del; p.Phe42LeufsTer19 variant (also known as Phe41fs when numbered from the mature protein or as codon 41/42-TTCT, rs80356821, HbVar ID: 849) has been reported in the homozygous and compound heterozygous states in individuals affected with beta(0) thalassemia (see link to HbVar, Kimura 1983). It is reported as pathogenic by multiple laboratories in ClinVar (Variation ID: 15417) and is observed in the general population at an overall frequency of 0.02% (73/282786 alleles) with increased frequency in the East Asian population (0.2%) in the Genome Aggregation Database. This variant creates a frameshift by deleting 4 nucleotides, so it is predicted to result in a truncated protein or mRNA subject to nonsense-mediated decay. Based on available information, this variant is considered to be pathogenic. References: Link to HbVar: https://globin.bx.psu.edu/hbvar/hbvar.html Kimura A et al. Structural analysis of a beta-thalassemia gene found in Taiwan. J Biol Chem. 1983 Mar 10;258(5):2748-9. PMID: 6826539. -
Pathogenic, criteria provided, single submitterclinical testingRevvity Omics, RevvityJan 06, 2020- -
Pathogenic, criteria provided, single submitterclinical testingGeneDxNov 03, 2021Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 20181291, 22975760, 6826539, 11224481, 24200214, 28635337, 26096776, 30487145, 30945812, 31111750, 31930713, 30275481, 10870880, 33198537, 8091935) -
Pathogenic, criteria provided, single submitterclinical testingClinical Genetics and Genomics, Karolinska University HospitalAug 29, 2017- -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 31, 2024This sequence change creates a premature translational stop signal (p.Phe42Leufs*19) in the HBB gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in HBB are known to be pathogenic (PMID: 23637309). This variant is present in population databases (rs281864900, gnomAD 0.2%). This premature translational stop signal has been observed in individuals with HBB-related conditions (PMID: 6826539, 25089872, 28635337). ClinVar contains an entry for this variant (Variation ID: 15417). For these reasons, this variant has been classified as Pathogenic. -
beta Thalassemia Pathogenic:5Other:1
not provided, no classification providedliterature onlyGeneReviews-- -
Pathogenic, no assertion criteria providedcurationThe ITHANET community portal, The Cyprus Institute of Neurology and GeneticsNov 25, 2019- -
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpApr 12, 2016Variant summary: The c.126_129delCTTT variant results in a premature termination codon, predicted to cause a truncated or absent HBB protein, which is a commonly known mechanism for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory (e.g.c.135delC, c.143_146dupATCT). Mutation taster predicts damaging outcome for this variant. This variant is found in 33/121370 control chromosomes at a frequency of 0.0002719, which does not exceed maximal expected frequency of a pathogenic allele (0.0111803). This variant is reported in the literatures as a well-known pathogenic variant predominantly identified in East and South Asian. In addition, multiple reputable databases classified this variant as pathogenic. Taken together, this variant was classified as pathogenic. -
Likely pathogenic, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaOct 31, 2018The HBB c.126_129delCTTT (p.Phe42LeufsTer19) variant, also described as codon 41/42 (-CTTT) or codon 41/42 (-TTCT), results in a frameshift and is predicted to result in premature truncation of the protein. This variant is particularly prevalent in the Chinese population and is usually associated with a beta-thalassemia phenotype (Lin et al. 2014; Zhang et al. 2015; Yu et al. 2015; Origa et al 2015). Across a selection of the available literature, the p.Phe42LeufsTer19 variant has been identified in a homozygous state in one individual and in a compound heterozygous state in seven individuals, all with beta-thalassemia (Kimura et al. 1983; Hernanda et al. 2012; Huang et al. 2014; Italia et al. 2015; Rujito et al. 2015). Control data are unavailable for this variant, which is reported at a frequency of 0.00496 in the East Asian population of the 1000 Genomes. Based on the evidence and the potential impact of frameshift variants, the p.Phe42LeufsTer19 variant is interpreted as pathogenic for beta-thalassemia. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -
Pathogenic, criteria provided, single submitterclinical testingMyriad Genetics, Inc.Dec 09, 2019NM_000518.4(HBB):c.126_129delCTTT(F42Lfs*19) is classified as pathogenic in the context of Hb beta chain-related hemoglobinopathy; it is associated with beta thalassemia and is classified as a beta-zero variant. Sources cited for classification include the following: PMID 6826539, 25000193, 6714226 and 25480500. Classification of NM_000518.4(HBB):c.126_129delCTTT(F42Lfs*19) is based on the following criteria: The variant causes a premature termination codon that is expected to be targeted by nonsense-mediated mRNA decay and is reported in individuals with the relevant phenotype. Please note: this variant was assessed in the context of healthy population screening. -
Pathogenic, no assertion criteria providedclinical testingNatera, Inc.Mar 17, 2017- -
Beta-thalassemia HBB/LCRB Pathogenic:4
Pathogenic, criteria provided, single submitterclinical testingLifecell International Pvt. Ltd-A Heterozygous Frameshift variant c.126_129delCTTT in Exon 2 of the HBB gene that results in the premature termination of the protein (p.Phe42fs*19) was identified. The observed variant has a minor allele frequency of 0.00028% in gnomAD exomes and genomes, respectively. The severity of the impact of this variant on the protein is high, based on the effect ofthe protein and REVEL score . Rare Exome Variant Ensemble Learner (REVEL) is an ensembl method for predicting the pathogenicity of missense variants based on a combination ofscores from 13 individual tools: MutPred, FATHMM v2.3, VEST 3.0, PolyPhen-2, SIFT, PROVEAN, MutationAssessor, MutationTaster, LRT, GERP++, SiPhy, phyloP, and phastCons.The REVEL score for an individual missense variant can range from 0 to 1, with higher scores reflecting greater likelihood that the variant is disease-causing. The variant was found inClinVar (Variant ID :15417) with a classification of Pathogenic/Likely Pathogenic and a review status of (2 star) criteria provided, multiple submitters, no conflicts. The variant is reported in many patients with beta thalassemia (Chen W et al.,2010). Based on the above evidence this variant has been classified as Pathogenic according to the ACMG guidelines. -
Pathogenic, criteria provided, single submitterclinical testingNeuberg Centre For Genomic Medicine, NCGM-This variant c.126_129del (p.Phe42LeufsTer19) in HBB gene has been observed in the homozygous and compound heterozygous state in several individuals with HBB-related conditions (Kimura A et al., 1983). This sequence change creates a premature translational stop signal (p.Phe42Leufs*19) in the HBB gene. It is expected to result in an absent or disrupted protein product. This variant is present in the gnomAD database with a frequency of 0.03%. Loss-of-function variants in HBB are known to be pathogenic (Craig JE et al., 1994). This variant has been reported to the ClinVar database as Pathogenic. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingGenetics and Molecular Pathology, SA PathologyNov 04, 2021- -
Pathogenic, no assertion criteria providedclinical testingMOLECULAR BIOLOGY AND HUMAN GENETICS DIVISION, THE UNIVERSITY OF BURDWANMay 07, 2024The HBB c.126_129delCTTT (NP_000509.1:p.Phe42fs ) is a frameshift variant leads to a premature termination of HBB mRNA. The variant also describe as beta0 mutation, When this variant present in homozygous or in compound heterozygous with other pathogenic HBB mutation leads to severe anemia, The condition known as beta thalassemia major. The frequency of this variant among thalassemia patient in Eastern India is 2.68 % as per our multicentric project - A Genetic Diagnostic Algorithm Based Study for Thalassemia in Northern and Eastern Indian Populations", Funded by Dept. of Biotechnology , Govt of India [Project No. BT/PR26461/MED/12/821/2018] -
Beta zero thalassemia Pathogenic:1
Pathogenic, no assertion criteria providedliterature onlyOMIMSep 28, 2002- -
Inborn genetic diseases Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingAmbry GeneticsNov 25, 2015The c.126_129delCTTT pathogenic mutation (also known as codons 41/42 (-TTCT) and c.124_127delTTCT), located in coding exon 2 of the HBB gene, results from a deletion of 4 nucleotides between positions 126 and 129, causing a translational frameshift with a predicted alternate stop codon (p.F42Lfs*19). This mutation is associated with beta0-thalassemia and was originally reported as homozygous in a Chinese patient (Kimura A et al. J Biol Chem. 1983;258(5):2748-9). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -
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 GeneticsMar 08, 2022- -
Fetal hemoglobin quantitative trait locus 1 Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingInstitute of Human Genetics, University of Leipzig Medical CenterJan 01, 2019- -
HBB-related disorder Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesJan 09, 2024The HBB c.126_129delCTTT variant is predicted to result in a frameshift and premature protein termination (p.Phe42Leufs*19). This variant was reported in individuals with beta-thalassemia (see for example Kazazian et al. 1984. PubMed ID: 6714226; Lau et al. 1997. PubMed ID: 9113933; Lin et al. 2021. PubMed ID: 34271589). This variant is reported in 0.23% of alleles in individuals of East Asian descent in gnomAD. Frameshift variants in HBB are expected to be pathogenic. This variant is interpreted as pathogenic. -
Hb SS disease Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingBaylor Genetics-- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

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

LitVar

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

Other links and lift over

dbSNP: rs80356821; hg19: chr11-5247992; API