2-86789325-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_001768.7(CD8A):c.623A>T(p.His208Leu) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000024 in 1,584,158 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00017 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000084 ( 0 hom. )

Consequence

CD8A
NM_001768.7 missense, splice_region

Scores

Splicing: ADA: 0.002299

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: -0.541

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 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.26415968).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CD8A	NM_001768.7 linkuse as main transcript	c.623A>T	p.His208Leu	missense_variant, splice_region_variant	4/6	ENST00000283635.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CD8A	ENST00000283635.8 linkuse as main transcript	c.623A>T	p.His208Leu	missense_variant, splice_region_variant	4/6	1	NM_001768.7	P1	P01732-1

Frequencies

GnomAD3 genomes

AF:

0.000171

AC:

AN:

152082

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000628

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000278

AC:

AN:

251416

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135916

show subpopulations

Gnomad AFR exome

AF:

0.000431

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000838

AC:

AN:

1432076

Hom.:

Cov.:

AF XY:

0.00000700

AC XY:

AN XY:

714194

show subpopulations

Gnomad4 AFR exome

AF:

0.000303

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:

0.00

Gnomad4 OTH exome

AF:

0.0000336

GnomAD4 genome

AF:

0.000171

AC:

AN:

152082

Hom.:

Cov.:

AF XY:

0.000162

AC XY:

AN XY:

74294

show subpopulations

Gnomad4 AFR

AF:

0.000628

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.000227

ESP6500AA

AF:

0.000454

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000330

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Susceptibility to respiratory infections associated with CD8alpha chain mutation

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Jul 20, 2022	This sequence change replaces histidine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 208 of the CD8A protein (p.His208Leu). This variant is present in population databases (rs146994832, gnomAD 0.07%). 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: 625911). 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: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C25"). 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Center for Genomics, Ann and Robert H. Lurie Children's Hospital of Chicago	Mar 30, 2021	CD8A NM_001768.6 exon 4 p.His208Leu (c.623A>T): This variant has not been reported in the literature but is present in 0.06% (16/24958) of African alleles in the Genome Aggregation Database (http://gnomad.broadinstitute.org/variant/2-87016448-T-A). Evolutionary conservation for this variant is limited or unavailable; computational predictive tools suggest that this variant may not impact the protein. In summary, data on this variant is insufficient for disease classification. Therefore, the clinical significance of this variant is uncertain. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.16

BayesDel_addAF

Benign

-0.30

BayesDel_noAF

Benign

-0.26

Cadd

Benign

Dann

Benign

0.88

DEOGEN2

Pathogenic

0.84

D;D;T

Eigen

Benign

-0.62

Eigen_PC

Benign

-0.89

FATHMM_MKL

Benign

0.13

M_CAP

Benign

0.061

MetaRNN

Benign

0.26

T;T;T

MetaSVM

Benign

-0.30

MutationAssessor

Uncertain

2.6

M;M;.

MutationTaster

Benign

1.0

N;N;N;N;N;N

PROVEAN

Pathogenic

-5.7

D;D;D

REVEL

Uncertain

0.39

Sift

Benign

0.030

D;D;D

Sift4G

Uncertain

0.059

T;T;T

Polyphen

0.98

D;D;.

Vest4

0.41

MVP

0.80

MPC

1.1

ClinPred

0.58

GERP RS

-4.9

Varity_R

0.21

gMVP

0.46

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.0023

dbscSNV1_RF

Benign

0.088

SpliceAI score (max)

0.080

Details are displayed if max score is > 0.2

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