chr11-5225605-T-C

Variant names:

• chr11-5225605-T-C
• rs35117167
• NM_000518.5:c.437A>G

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_000518.5(HBB):​c.437A>G​(p.Tyr146Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y146N) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: HBB NM_000518.5 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3 O:1
• Conservation: PhyloP100: 7.21
• Publications: 4 publications found

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

ENSG00000298932 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PM1: In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 25 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 chr11-5225606-A-T is described in ClinVar as Pathogenic. ClinVar VariationId is 633256.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.978
• PP5: Variant 11-5225605-T-C is Pathogenic according to our data. Variant chr11-5225605-T-C is described in ClinVar as Pathogenic. ClinVar VariationId is 15322.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HBB	NM_000518.5	c.437A>G	p.Tyr146Cys	missense_variant	Exon 3 of 3	ENST00000335295.4	NP_000509.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HBB	ENST00000335295.4	c.437A>G	p.Tyr146Cys	missense_variant	Exon 3 of 3	1	NM_000518.5	ENSP00000333994.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000653 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Nov 11, 2019

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not found in the total gnomAD dataset, and the data is high quality. Conflicting predictions of the effect on the protein. Other pathogenic or likely pathogenic variants affect the same amino acid. Assessment of experimental evidence suggests this variant results in abnormal protein function. Very strong co-segregation with disease, and data include affected and unaffected individuals from multiple families. -

Apr 21, 2020

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The Hb Rainier variant (HBB: c.437A>G; p.Tyr146Cys, also known as Tyr145Cys when numbered from the mature protein, rs35117167) is reported in the literature in the heterozygous state in multiple individuals affected with erythrocytosis (see link to HbVar and references therein, Adamson 1969). This variant is reported in ClinVar (Variation ID: 15322), and is absent from general population databases (Exome Variant Server, Genome Aggregation Database), indicating it is not a common polymorphism. The tyrosine at codon 146 is highly conserved, and functional analyses of the variant protein show increased oxygen affinity (see link to HbVar, Adamson 1969). Additionally, other amino acid substitutions at this codon (Hb Nancy, Hb Osler, Hb Bethesda, Hb McKees Rocks) have been reported in individuals with erythrocytosis and are considered pathogenic (HbVar IDs: 570, 572, 573, 574), and several hemoglobin variants with high oxygen affinity leading to erythrocytosis are located at the carboxy-terminal end of the HBB gene (Wajcman 2004). Based on available information, the Hb Rainier variant is considered to be pathogenic. References: Link to HbVar for Hb Rainier: http://globin.bx.psu.edu/cgi-bin/hbvar/query_vars3?mode=output&display_format=page&i=571 Adamson JW et al. Erythrocytosis associated with hemoglobin Rainier: oxygen equilibria and marrow regulation. J Clin Invest. 1969 Aug;48(8):1376-86. Wajcman H and Galacteros F. Hemoglobins with high oxygen affinity leading to erythrocytosis. New variants and new concepts. Hemoglobin. 2005;29(2):91-106. -

Erythrocytosis, familial, 6 Pathogenic:1

May 01, 1999

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

HEMOGLOBIN RAINIER 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	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.51
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.36	T;T
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	.;D
M_CAP	Pathogenic	0.82	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.2	H;H
PhyloP100		7.2
PrimateAI	Uncertain	0.74	T
PROVEAN	Pathogenic	-6.9	D;.
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D;.
Sift4G	Pathogenic	0.0010	D;.
Polyphen		1.0	D;D
Vest4		0.89
MutPred		0.85		Loss of ubiquitination at K145 (P = 0.0343);Loss of ubiquitination at K145 (P = 0.0343);
MVP		0.95
MPC		0.28
ClinPred		0.99	D
GERP RS		4.7
Varity_R		0.81
gMVP		0.96
Mutation Taster		=3/97	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs35117167; hg19: chr11-5246835;