rs1555613692

Variant names:

• chr17-44378360-A-G
• rs1555613692
• NM_000419.5:c.2094+2T>C

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2_Supporting PM3_Supporting

This summary comes from the ClinGen Evidence Repository: The NM_000419.5(ITGA2B):c.2094+2T>C splice variant is predicted to cause skipping of exon 20, introducing a premature termination codon, and the resulting mRNA product is predicted to undergo nonsense mediated decay, leading to loss of normal protein function. This variant has been observed in homozygosity in one individual reported to have Glanzmann's thrombasthenia (GT), however sufficient phenotype information was not provided to determine if the individual's phenotype is specific for GT. This variant is absent from population databases, including gnomAD. In summary, this variant meets criteria to be classified as pathogenic for GT. GT-specific criteria applied: PVS1, PM2_Supporting, and PM3_supporting. LINK:https://erepo.genome.network/evrepo/ui/classification/CA399799489/MONDO:0010119/011

• Frequency: Genomes: not found (cov: 32)
• Consequence: ITGA2B NM_000419.5 splice_donor, intron
• Scores: Splicing: ADA: 0.9851
• Clinical Significance: Pathogenic reviewed by expert panel P:2
• Conservation: PhyloP100: 5.46
• 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: ClinGen, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• Glanzmann thrombasthenia

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

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics
• 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: Pathogenic. The variant received 10 ACMG points.

• PVS1: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PM3: 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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ITGA2B	NM_000419.5	MANE Select	c.2094+2T>C		splice_donor intron	N/A	NP_000410.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ITGA2B	ENST00000262407.6	TSL:1 MANE Select	c.2094+2T>C		splice_donor intron	N/A	ENSP00000262407.5
	ITGA2B	ENST00000648408.1		c.1524+2T>C		splice_donor intron	N/A	ENSP00000498119.1
	ITGA2B	ENST00000592462.5	TSL:5	n.889+2T>C		splice_donor intron	N/A

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
2	-	-	Glanzmann thrombasthenia (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	-0.060
CADD	Uncertain	24
DANN	Benign	0.97
Eigen	Pathogenic	0.90
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Pathogenic	0.97	D
PhyloP100		5.5
GERP RS		5.3
Mutation Taster		=6/94	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.99
dbscSNV1_RF	Benign	0.71
SpliceAI score (max)		0.70		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.70		Position offset: 2

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

Other links and lift over

dbSNP: rs1555613692; hg19: chr17-42455728;