rs34264694

Variant names:

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 8P and 2B. PM1PM2PP3_StrongBP6_Moderate

The NM_000184.3(HBG2):c.199A>C(p.Lys67Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,892 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 Likely benign (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K67R) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 31)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

HBG2
NM_000184.3 missense

Scores

Clinical Significance

Likely benign criteria provided, single submitter B:1O:1

Conservation

PhyloP100: 3.00

Publications

1 publications found

Variant links:

Genes affected

HBG2 (HGNC:4832): (hemoglobin subunit gamma 2) The gamma globin genes (HBG1 and HBG2) are normally expressed in the fetal liver, spleen and bone marrow. Two gamma chains together with two alpha chains constitute fetal hemoglobin (HbF) which is normally replaced by adult hemoglobin (HbA) at birth. In some beta-thalassemias and related conditions, gamma chain production continues into adulthood. The two types of gamma chains differ at residue 136 where glycine is found in the G-gamma product (HBG2) and alanine is found in the A-gamma product (HBG1). The former is predominant at birth. 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]

HBG2 Gene-Disease associations (from GenCC):

hemoglobinopathy Toms River
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
hereditary persistence of fetal hemoglobin-beta-thalassemia syndrome
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
hereditary persistence of fetal hemoglobin-sickle cell disease syndrome
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
cyanosis, transient neonatal
Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

HBG2 links:

ENSG00000284931 (HGNC:):

ENSG00000284931 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM1

In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain in NM_000184.3

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.964

BP6

Variant 11-5254408-T-G is Benign according to our data. Variant chr11-5254408-T-G is described in ClinVar as Likely_benign. ClinVar VariationId is 14987.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HBG2	NM_000184.3 link	c.199A>C	p.Lys67Gln	missense_variant	Exon 2 of 3	ENST00000336906.6	NP_000175.1	P69892D9YZU9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
HBG2	ENST00000336906.6 link	c.199A>C	p.Lys67Gln	missense_variant	Exon 2 of 3	1	NM_000184.3	ENSP00000338082.4	P69892
ENSG00000284931	ENST00000642908.1 link	c.199A>C	p.Lys67Gln	missense_variant	Exon 2 of 3			ENSP00000495346.1
ENSG00000239920	ENST00000380259.7 link	n.*1502A>C		non_coding_transcript_exon_variant	Exon 8 of 8	5		ENSP00000369609.3	A0A2U3TZJ3
ENSG00000239920	ENST00000380259.7 link	n.*1502A>C		3_prime_UTR_variant	Exon 8 of 8	5		ENSP00000369609.3	A0A2U3TZJ3

Frequencies

GnomAD3 genomes

Cov.:

GnomAD2 exomes

AF:

0.0000159

AC:

AN:

251490

AF XY:

0.0000147

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000116

Gnomad ASJ exome

AF:

0.00

Gnomad EAS 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:

0.00000342

AC:

AN:

1461892

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727248

show subpopulations

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.00

AC:

AN:

33480

American (AMR)

AF:

0.000112

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.00

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53420

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1112010

Other (OTH)

AF:

0.00

AC:

AN:

60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.265

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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

Cov.:

Alfa

AF:

0.00

Hom.:

ClinVar

Significance: Likely benign

Submissions summary: Benign:1Other:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Benign:1

Jul 02, 2021

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

HEMOGLOBIN F (BROOKLYN)

Other:1

Aug 05, 2011

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

Pathogenic

0.59

BayesDel_addAF

Benign

0.0018

BayesDel_noAF

Uncertain

-0.040

CADD

Uncertain

(source)

DANN

Uncertain

0.99

DEOGEN2

Benign

0.12

.;.;T;.

Eigen

Uncertain

0.65

Eigen_PC

Uncertain

0.47

FATHMM_MKL

Uncertain

0.94

LIST_S2

Pathogenic

0.98

D;D;D;D

M_CAP

Uncertain

0.12

MetaRNN

Pathogenic

0.96

D;D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

3.6

.;.;H;.

PhyloP100

3.0

PROVEAN

Uncertain

-3.6

.;.;D;.

REVEL

Uncertain

0.60

Sift

Pathogenic

0.0

.;.;D;.

Sift4G

Uncertain

0.0080

.;.;D;.

Polyphen

1.0

.;.;D;.

Vest4

0.60

MutPred

0.92

Gain of catalytic residue at K67 (P = 0.0412);Gain of catalytic residue at K67 (P = 0.0412);Gain of catalytic residue at K67 (P = 0.0412);.;

MVP

0.97

ClinPred

0.98

GERP RS

4.0

PromoterAI

-0.043

Neutral

(source)

RBP_binding_hub_radar

1.1

RBP_regulation_power_radar

3.0

Varity_R

0.95

gMVP

0.61

Mutation Taster

=27/73

disease causing

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over