rs77961246

Variant summary

Our verdict is Pathogenic. The variant received 15 ACMG points: 15P and 0B. PM2PP2PP3_StrongPP5_Very_Strong

The NM_000419.5(ITGA2B):​c.2113T>C​(p.Cys705Arg) variant causes a missense change. The variant allele was found at a frequency of 0.0000031 in 1,613,360 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 Pathogenic (★★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 30)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

ITGA2B
NM_000419.5 missense

Scores

13
4
2

Clinical Significance

Pathogenic reviewed by expert panel P:2

Conservation

PhyloP100: 7.06

Publications

5 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 15 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 73 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. Gene score misZ: 1.2307 (below the threshold of 3.09). Trascript score misZ: 1.3195 (below the threshold of 3.09). GenCC associations: The gene is linked to Glanzmann's thrombasthenia, autosomal dominant macrothrombocytopenia, platelet-type bleeding disorder 16, Glanzmann thrombasthenia 1, Glanzmann thrombasthenia.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.993
PP5
Variant 17-44377772-A-G is Pathogenic according to our data. Variant chr17-44377772-A-G is described in ClinVar as Pathogenic. ClinVar VariationId is 953058.Status of the report is reviewed_by_expert_panel, 3 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ITGA2BNM_000419.5 linkc.2113T>C p.Cys705Arg missense_variant Exon 21 of 30 ENST00000262407.6 NP_000410.2 P08514-1
ITGA2BXM_011524749.2 linkc.2266T>C p.Cys756Arg missense_variant Exon 21 of 29 XP_011523051.2 P08514
ITGA2BXM_011524750.2 linkc.2266T>C p.Cys756Arg missense_variant Exon 21 of 29 XP_011523052.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ITGA2BENST00000262407.6 linkc.2113T>C p.Cys705Arg missense_variant Exon 21 of 30 1 NM_000419.5 ENSP00000262407.5 P08514-1
ITGA2BENST00000648408.1 linkc.1543T>C p.Cys515Arg missense_variant Exon 17 of 25 ENSP00000498119.1 A0A3B3IU79
ITGA2BENST00000592462.5 linkn.908T>C non_coding_transcript_exon_variant Exon 10 of 15 5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152108
Hom.:
0
Cov.:
30
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251428
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461252
Hom.:
0
Cov.:
32
AF XY:
0.00000275
AC XY:
2
AN XY:
726936
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:
0
AN:
33458
American (AMR)
AF:
0.00
AC:
0
AN:
44706
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39680
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86248
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53352
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5760
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1111576
Other (OTH)
AF:
0.00
AC:
0
AN:
60342
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000173310), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.400
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152108
Hom.:
0
Cov.:
30
AF XY:
0.00
AC XY:
0
AN XY:
74286
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41400
American (AMR)
AF:
0.00
AC:
0
AN:
15258
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:2
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

Glanzmann thrombasthenia Pathogenic:1
Sep 06, 2020
ClinGen Platelet Disorders Variant Curation Expert Panel, ClinGen
Significance:Pathogenic
Review Status:reviewed by expert panel
Collection Method:curation

The c.2113T>C (p.Cys705Arg) variant has been reported in at least 7 probands (3 homozygotes and 4 compound heterozygotes; PMIDs: 20020534, 12424194, 12083483, 25728920, 25539746, 9920835); at least two with a phenotype highly specific to GT (PMIDs: 9920835, 25539746). The variant cosegregated with disease in one of these probands and two additional relatives (PMID: 12424194). The variant is found at an extremely low frequency, with an the overall allele frequency on gnomAD is 0.000003977 (1/113,742 alleles in the non-Finnish European population). Multiple lines of computational evidence support a deleterious effect on the gene/gene product (REVEL score of 0.878). Expression in CHO cells was strongly attenuated, shown by immunoprecipitation and flow cytometry (~70% reduction), in cells coexpressing normal GPIIIa with the mutant GPIIb. In summary, this variant meets criteria to be classified as Pathogenic for GT. GT-specific criteria applied: PM2_Supporting, PM3_Strong, PP1_Moderate, PP3, and PP4_Strong. -

Glanzmann thrombasthenia 1 Pathogenic:1
-
ISTH-SSC Genomics in Thrombosis and Hemostasis, KU Leuven, Center for Molecular and Vascular Biology
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.45
D
BayesDel_noAF
Pathogenic
0.41
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.45
T
Eigen
Pathogenic
0.87
Eigen_PC
Pathogenic
0.81
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.71
T
M_CAP
Pathogenic
0.47
D
MetaRNN
Pathogenic
0.99
D
MetaSVM
Uncertain
0.69
D
MutationAssessor
Pathogenic
3.5
H
PhyloP100
7.1
PrimateAI
Uncertain
0.73
T
PROVEAN
Pathogenic
-11
D
REVEL
Pathogenic
0.88
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.98
MutPred
0.94
Gain of MoRF binding (P = 0.0014);
MVP
0.91
MPC
1.3
ClinPred
1.0
D
GERP RS
5.6
Varity_R
0.99
gMVP
0.92
Mutation Taster
=0/100
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs77961246; hg19: chr17-42455140; API