NM_000419.5:c.*165T>C

Variant names:

• chr17-44372199-A-G
• rs2143416246
• NM_000419.5:c.*165T>C

Variant summary

Our verdict is Uncertain significance. The variant received 6 ACMG points: 6P and 0B. PP4_Strong PM2_Supporting PM3_Supporting

This summary comes from the ClinGen Evidence Repository: The NM_000419.5(ITGA2B):c.*165T>C 3'UTR variant was identified homozygous (PM3_supporting) in at least one patient (GT75 in PMID:25728920) who displayed mucocutaneous bleeding and impaired aggregation with all agonists except ristocetin, which is highly specific for Glanzmann thrombasthenia. Additionally, αIIbβ3 surface expression was reduced to <5%, as measured by flow cytometry (PP4_strong). This variant is absent from gnomAD v4.1 (PM2_Supporting). ACMG/AMP criteria applied, as specified by the ClinGen PD VCEP: PP4_strong, PM2_supporting, PM3_supporting. (VCEP specifications version 2.1). These criteria reach Likely Pathogenic however, to our knowledge, there is no known disease mechanism for 3'UTR variants in Glanzmann thrombasthenia. In the absence of additional cases or functional data the ClinGen PD VCEP classifies this variant as uncertain significance for autosomal recessive Glanzmann Thrombasthenia. LINK:https://erepo.genome.network/evrepo/ui/classification/CA915940530/MONDO:0100326/011

• Frequency: Genomes: not found (cov: 31)
• Consequence: ITGA2B NM_000419.5 3_prime_UTR
• Clinical Significance: Uncertain significance reviewed by expert panel U:1
• Conservation: PhyloP100: 4.07
• Publications: 0 publications found

Genes affected

ITGA2B (HGNC:6138): (integrin subunit alpha 2b) This gene encodes a member of the integrin alpha chain family of proteins. The encoded preproprotein is proteolytically processed to generate light and heavy chains that associate through disulfide linkages to form a subunit of the alpha-IIb/beta-3 integrin cell adhesion receptor. This receptor plays a crucial role in the blood coagulation system, by mediating platelet aggregation. Mutations in this gene are associated with platelet-type bleeding disorders, which are characterized by a failure of platelet aggregation, including Glanzmann thrombasthenia. [provided by RefSeq, Jan 2016]

ITGA2B Gene-Disease associations (from GenCC):

• platelet-type bleeding disorder 16

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, ClinGen
• Glanzmann thrombasthenia

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• Glanzmann's thrombasthenia

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet
• Glanzmann thrombasthenia 1

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• autosomal dominant macrothrombocytopenia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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

• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PM3: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000419.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ITGA2B	NM_000419.5	MANE Select	c.*165T>C		3_prime_UTR	Exon 30 of 30	NP_000410.2	P08514-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ITGA2B	ENST00000262407.6	TSL:1 MANE Select	c.*165T>C		3_prime_UTR	Exon 30 of 30	ENSP00000262407.5	P08514-1
	ITGA2B	ENST00000901307.1		c.*165T>C		3_prime_UTR	Exon 29 of 29	ENSP00000571366.1
	ITGA2B	ENST00000949677.1		c.*165T>C		3_prime_UTR	Exon 29 of 29	ENSP00000619736.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 6

GnomAD4 genome Cov.: 31

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
-	1	-	Glanzmann thrombasthenia (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.45
CADD	Benign	18
DANN	Benign	0.82
PhyloP100		4.1
Mutation Taster		=20/80	disease causing

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

Other links and lift over

dbSNP: rs2143416246; hg19: chr17-42449567;