NM_000518.5:c.93-15T>G

Variant names:

• chr11-5226814-A-C
• rs35456885
• NM_000518.5:c.93-15T>G

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM2 PP3_Moderate PP5_Very_Strong

The NM_000518.5(HBB):​c.93-15T>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,458,928 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: HBB NM_000518.5 intron
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:7
• Conservation: PhyloP100: -0.520
• Publications: 3 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 12 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 11-5226814-A-C is Pathogenic according to our data. Variant chr11-5226814-A-C is described in ClinVar as Pathogenic. ClinVar VariationId is 550356.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.93-15T>G		intron_variant	Intron 1 of 2	ENST00000335295.4	NP_000509.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HBB	ENST00000335295.4	c.93-15T>G		intron_variant	Intron 1 of 2	1	NM_000518.5	ENSP00000333994.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1458928 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 725976

African (AFR) AF: 0.00 AC: 0 AN: 33416

American (AMR) AF: 0.00 AC: 0 AN: 44714

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26126

East Asian (EAS) AF: 0.00 AC: 0 AN: 39670

South Asian (SAS) AF: 0.00 AC: 0 AN: 86210

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5750

European-Non Finnish (NFE) AF: 9.01e-7 AC: 1 AN: 1109340

Other (OTH) AF: 0.00 AC: 0 AN: 60286

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

beta Thalassemia Pathogenic:3

Nov 25, 2019

The ITHANET community portal, The Cyprus Institute of Neurology and Genetics

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: curation

- -

Nov 02, 2022

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: HBB c.93-15T>G alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 2/4 computational tools predict this variant creates cryptic 3' acceptor site. At least one publication reports experimental evidence that this variant affects mRNA splicing. Transient expression studies revealed a 4-fold decrease in the amount of RNA produced with > 99% of it being abnormally spliced (example: Metherall_1986). The variant was absent in 251042 control chromosomes (gnomAD). c.93-15T>G has been reported in the literature in multiple compound heterozygote and homozygote individuals affected with Beta Thalassemia (example: Metherall_1986, Chouk_2004 and Jarjour_2014). These data indicate that the variant is very likely to be associated with disease. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and all laboratories classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Mar 17, 2017

Natera, Inc.

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Beta-thalassemia HBB/LCRB Pathogenic:2

Jan 10, 2017

Counsyl

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Feb 01, 2024

Laboratory of Medical Genetics, National & Kapodistrian University of Athens

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: curation

- -

Beta zero thalassemia Pathogenic:1

Oct 01, 1986

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

not provided Pathogenic:1

Dec 14, 2024

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Non-canonical splice site variant demonstrated to result in loss of function (PMID: 3780671); Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 3780671, 20704537, 20863160, 15108284, 18096416, 15481885, 31286593, 24828949, 9495372, 27785405, 34794358, Sheth2022[CaseReport], 27351925) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	0.59
DANN	Benign	0.65
PhyloP100		-0.52
PromoterAI		-0.030	Neutral
Mutation Taster		=33/67	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.92		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.92		Position offset: -1
DS_AL_spliceai		0.80		Position offset: -15

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs35456885; hg19: chr11-5248044;