rs34439278

Variant names:

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PM5PP3_Moderate

The NM_000518.5(HBB):c.170G>A(p.Gly57Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,874 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G57R) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Failed GnomAD Quality Control

Consequence

HBB
NM_000518.5 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:2

Conservation

PhyloP100: 0.0160

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr11-5226723-C-G is described in Lovd as [Pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.898

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HBB	NM_000518.5 link	c.170G>A	p.Gly57Asp	missense_variant	Exon 2 of 3	ENST00000335295.4	NP_000509.1	P68871D9YZU5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HBB	ENST00000335295.4 link	c.170G>A	p.Gly57Asp	missense_variant	Exon 2 of 3	1	NM_000518.5	ENSP00000333994.3		P68871

Frequencies

GnomAD3 genomes

AF:

0.00

AC:

AN:

152092

Hom.:

Cov.:

FAILED QC

Gnomad AFR

AF:

0.00

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:

0.0000199

AC:

AN:

251448

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135892

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000272

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:

0.00000137

AC:

AN:

1461874

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

727244

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000504

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

Data not reliable, filtered out with message: AC0;AS_VQSR

AF:

0.00

AC:

AN:

152092

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74300

Gnomad4 AFR

AF:

0.00

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

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2Benign:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not specified

Uncertain:1Benign:1

Apr 16, 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.170G>A (p.Gly57Asp) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2e-05 in 251448 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.170G>A was identified in the literature in heterozygous carriers who were clinically normal (e.g. Blackwell_1966, Pootrakul_1967). It has also been reported in the compound heterozygous state with pathogenic variants in individuals with some features of Beta Thalassemia as well as in clinically normal indivduals (e.g. Honig_1982, Chang_2002, Fucharoen_2001, 2005, Zhang_2017). These reports 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. The following publications have been ascertained in the context of this evaluation (PMID: 12403500, 6252122, 6025242, 5967288, 19631632, 19460936, 20838957, 6859036, 5970505, 5415584, 21599435, 7216820, 15938724, 11422410, 4421749, 7161111, 28407371). ClinVar contains an entry for this variant (Variation ID: 15214). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Dec 12, 2017

OMIM

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: literature only

- -

not provided

Uncertain:1Benign:1

Sep 10, 2024

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The HBB c.170G>A (p.Gly57Asp) variant has been reported in the published literature to have normal stability and oxygen affinity (PMID: 7216820 (1981)), with normal clinical presentation in heterozygotes (PMIDs: 7216820 (1981), 6025242 (1967)). Compound heterozygous individuals carrying this variant and a beta+ thalassemia variant on the other allele presented as beta-thalassemia trait, suggesting this variant did not aggravate the phenotype (PMIDs: 23568723 (2013), 12403500 (2002), 1428942 (1992)). The frequency of this variant in the general population, 0.00025 (5/19946 chromosomes (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is uninformative in the assessment of its pathogenicity. Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is damaging. Based on the available information, we are unable to determine the clinical significance of this variant. -

Dec 06, 2023

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The Hb J-Bangkok variant (HBB: c.170G>A; p.Gly57Asp, also known as Gly56Asp when numbered from the mature protein, rs34439278, HbVar ID: 342), also known as Hb J-Meinung, is the most common stable variant found in Taiwanese individuals and has been reported in the heterozygous state in asymptomatic individuals with normal hematological parameters (Zhao 2013, HbVar and references therein). In individuals carrying a beta-+/0 variant, Hb J-Bangkok is not associated with more severe symptoms or hematology than those with the beta-+/0 variant alone (Chang 2002, Zhao 2013). The Hb J-Bangkok variant is reported in ClinVar (Variation ID: 15214) and is observed in the East Asian population at an overall frequency of 0.03% (5/19946 alleles) in the Genome Aggregation Database. The glycine at codon 56 is moderately conserved, computational analyses but are uncertain whether this variant is neutral or deleterious (REVEL: 0.636). Based on available information, this variant is considered likely benign. References: Link to HbVar: https://globin.bx.psu.edu/hbvar/hbvar.html Chang J et al. Hb G-Honolulu (alpha30(B11)Glu-->Gln (alpha2)), Hb J-Meinung (beta56(D7)Gly-->Asp), and beta-thalassemia (codons 41/42 (-TCTT)) in a Taiwanese family. Hemoglobin. 2002 Aug;26(3):325-8. PMID: 12403500. Zhao Y et al. Analysis of clinical phenotypes of compound heterozygotes of Hb J-Bangkok and ÃŸ-thalassemia. Zhonghua Yi Xue Yi Chuan Xue Za Zhi. 2013 Apr;30(2):148-51. PMID: 23568723. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.27

BayesDel_addAF

Uncertain

0.14

BayesDel_noAF

Pathogenic

0.27

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Benign

0.057

T;T;.;T

Eigen

Benign

-0.79

Eigen_PC

Benign

-0.91

FATHMM_MKL

Benign

0.13

LIST_S2

Benign

0.85

.;T;T;T

M_CAP

Pathogenic

0.48

MetaRNN

Pathogenic

0.90

D;D;D;D

MetaSVM

Uncertain

0.54

MutationAssessor

Uncertain

2.3

M;M;.;.

PrimateAI

Benign

0.41

PROVEAN

Uncertain

-3.8

D;.;.;D

REVEL

Uncertain

0.64

Sift

Uncertain

0.0030

D;.;.;D

Sift4G

Uncertain

0.037

D;.;.;.

Polyphen

0.017

B;B;.;.

Vest4

0.57

MutPred

0.81

Gain of ubiquitination at K60 (P = 0.0421);Gain of ubiquitination at K60 (P = 0.0421);Gain of ubiquitination at K60 (P = 0.0421);Gain of ubiquitination at K60 (P = 0.0421);

MVP

0.93

MPC

0.048

ClinPred

0.52

GERP RS

-2.8

Varity_R

0.39

gMVP

0.75

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over