chr17-44372383-T-A

Position:

• chr17-44372383-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_000419.5(ITGA2B):​c.3101A>T​(p.Asp1034Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: ITGA2B NM_000419.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.20

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM1: In a chain Integrin alpha-IIb light chain, form 1 (size 148) in uniprot entity ITA2B_HUMAN there are 8 pathogenic changes around while only 2 benign (80%) in NM_000419.5
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.2464931).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ITGA2B	NM_000419.5	c.3101A>T	p.Asp1034Val	missense_variant	30/30	ENST00000262407.6
ITGA2B	XM_011524749.2	c.3152A>T	p.Asp1051Val	missense_variant	29/29
ITGA2B	XM_011524750.2	c.3137A>T	p.Asp1046Val	missense_variant	29/29

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ITGA2B	ENST00000262407.6	c.3101A>T	p.Asp1034Val	missense_variant	30/30	1	NM_000419.5	P1
ITGA2B	ENST00000648408.1	c.2417A>T	p.Asp806Val	missense_variant	25/25
ITGA2B	ENST00000587295.5	c.296A>T	p.Asp99Val	missense_variant	3/3	3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Glanzmann thrombasthenia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 22, 2023

This sequence change replaces aspartic acid, which is acidic and polar, with valine, which is neutral and non-polar, at codon 1034 of the ITGA2B protein (p.Asp1034Val). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ITGA2B-related conditions. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.060	T
BayesDel_noAF	Benign	-0.32
CADD	Benign	21
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.47	T
Eigen	Benign	0.15
Eigen_PC	Benign	0.19
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Benign	0.59	T
M_CAP	Benign	0.059	D
MetaRNN	Benign	0.25	T
MetaSVM	Benign	-0.62	T
MutationAssessor	Benign	1.1	L
MutationTaster	Benign	1.0	D;D
PrimateAI	Benign	0.35	T
PROVEAN	Benign	-1.4	N
REVEL	Benign	0.17
Sift	Uncertain	0.0090	D
Sift4G	Uncertain	0.0050	D
Polyphen		0.62	P
Vest4		0.28
MutPred		0.52		Loss of helix (P = 0.0376);
MVP		0.66
MPC		0.57
ClinPred		0.69	D
GERP RS		4.4
Varity_R		0.19
gMVP		0.62

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr17-42449751;