2-86788530-C-T

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_001768.7(CD8A):c.656G>A(p.Arg219Gln) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000496 in 1,612,486 control chromosomes in the GnomAD database, with no homozygous occurrence. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000040 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000051 ( 0 hom. )

Consequence

CD8A
NM_001768.7 missense, splice_region

Scores

Splicing: ADA: 1.000

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.31

Variant links:

Genes affected

CD8A (HGNC:1706): (CD8 subunit alpha) The CD8 antigen is a cell surface glycoprotein found on most cytotoxic T lymphocytes that mediates efficient cell-cell interactions within the immune system. The CD8 antigen acts as a coreceptor with the T-cell receptor on the T lymphocyte to recognize antigens displayed by an antigen presenting cell in the context of class I MHC molecules. The coreceptor functions as either a homodimer composed of two alpha chains or as a heterodimer composed of one alpha and one beta chain. Both alpha and beta chains share significant homology to immunoglobulin variable light chains. This gene encodes the CD8 alpha chain. Multiple transcript variants encoding different isoforms have been found for this gene. The major protein isoforms of this gene differ by the presence or absence of a transmembrane domain and thus differ in being a membrane-anchored or secreted protein. [provided by RefSeq, May 2020]

CD8A links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CD8A	NM_001768.7 link	c.656G>A	p.Arg219Gln	missense_variant, splice_region_variant	Exon 5 of 6	ENST00000283635.8	NP_001759.3	P01732-1Q6ZVS2Q8TAW8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CD8A	ENST00000283635.8 link	c.656G>A	p.Arg219Gln	missense_variant, splice_region_variant	Exon 5 of 6	1	NM_001768.7	ENSP00000283635.3		P01732-1

Frequencies

GnomAD3 genomes

AF:

0.0000395

AC:

AN:

151794

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000485

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000193

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000279

AC:

AN:

250504

Hom.:

AF XY:

0.0000369

AC XY:

AN XY:

135354

show subpopulations

Gnomad AFR exome

AF:

0.000124

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000441

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000507

AC:

AN:

1460692

Hom.:

Cov.:

AF XY:

0.0000413

AC XY:

AN XY:

726608

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000639

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.0000395

AC:

AN:

151794

Hom.:

Cov.:

AF XY:

0.0000405

AC XY:

AN XY:

74090

show subpopulations

Gnomad4 AFR

AF:

0.0000485

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000193

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.00000516

Hom.:

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Susceptibility to respiratory infections associated with CD8alpha chain mutation

Uncertain:1

Jul 30, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 219 of the CD8A protein (p.Arg219Gln). This variant also falls at the last nucleotide of exon 5, which is part of the consensus splice site for this exon. This variant is present in population databases (rs138963205, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with CD8A-related conditions. ClinVar contains an entry for this variant (Variation ID: 941739). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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

0.21

BayesDel_addAF

Benign

-0.052

BayesDel_noAF

Uncertain

-0.080

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.83

.;D;D;T

Eigen

Pathogenic

0.72

Eigen_PC

Uncertain

0.66

FATHMM_MKL

Uncertain

0.85

LIST_S2

Benign

0.82

T;.;D;D

M_CAP

Uncertain

0.17

MetaRNN

Uncertain

0.71

D;D;D;D

MetaSVM

Uncertain

0.66

MutationAssessor

Pathogenic

3.0

.;M;M;.

PrimateAI

Uncertain

0.55

PROVEAN

Uncertain

-2.5

N;D;D;D

REVEL

Uncertain

0.58

Sift

Pathogenic

0.0

D;D;D;D

Sift4G

Pathogenic

0.0

D;D;D;D

Polyphen

1.0

D;D;D;.

Vest4

0.63

MutPred

0.56

.;Gain of sheet (P = 0.0085);Gain of sheet (P = 0.0085);.;

MVP

0.95

MPC

1.6

ClinPred

0.91

GERP RS

5.0

Varity_R

0.66

gMVP

0.29

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.97

SpliceAI score (max)

0.21

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.21

Position offset: 0

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over