chr16-28932085-G-C

Position:

chr16-28932085-G-C

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 2P and 3B. PM2BP4_ModerateBS1_Supporting

The NM_001770.6(CD19):c.85G>C(p.Glu29Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000242 in 1,613,400 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 31)

Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

CD19
NM_001770.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.35

Variant links:

Genes affected

CD19 (HGNC:1633): (CD19 molecule) This gene encodes a member of the immunoglobulin gene superfamily. Expression of this cell surface protein is restricted to B cell lymphocytes. This protein is a reliable marker for pre-B cells but its expression diminishes during terminal B cell differentiation in antibody secreting plasma cells. The protein has two N-terminal extracellular Ig-like domains separated by a non-Ig-like domain, a hydrophobic transmembrane domain, and a large C-terminal cytoplasmic domain. This protein forms a complex with several membrane proteins including complement receptor type 2 (CD21) and tetraspanin (CD81) and this complex reduces the threshold for antigen-initiated B cell activation. Activation of this B-cell antigen receptor complex activates the phosphatidylinositol 3-kinase signalling pathway and the subsequent release of intracellular stores of calcium ions. This protein is a target of chimeric antigen receptor (CAR) T-cells used in the treatment of lymphoblastic leukemia. Mutations in this gene are associated with the disease common variable immunodeficiency 3 (CVID3) which results in a failure of B-cell differentiation and impaired secretion of immunoglobulins. CVID3 is characterized by hypogammaglobulinemia, an inability to mount an antibody response to antigen, and recurrent bacterial infections. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jul 2020]

CD19 links:

RABEP2 (HGNC:24817): (rabaptin, RAB GTPase binding effector protein 2) Predicted to enable GTPase activator activity and growth factor activity. Involved in regulation of cilium assembly. Located in cytosol; intracellular membrane-bounded organelle; and microtubule organizing center. [provided by Alliance of Genome Resources, Apr 2022]

RABEP2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.12338582).

BS1

Variant frequency is greater than expected in population sas. gnomad4_exome allele frequency = 0.0000253 (37/1461096) while in subpopulation SAS AF= 0.000429 (37/86240). AF 95% confidence interval is 0.00032. There are 0 homozygotes in gnomad4_exome. There are 23 alleles in male gnomad4_exome subpopulation. Median coverage is 30. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CD19	NM_001770.6 linkuse as main transcript	c.85G>C	p.Glu29Gln	missense_variant	1/15	ENST00000538922.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CD19	ENST00000538922.8 linkuse as main transcript	c.85G>C	p.Glu29Gln	missense_variant	1/15	5	NM_001770.6	P3	P15391-1
CD19	ENST00000324662.8 linkuse as main transcript	c.85G>C	p.Glu29Gln	missense_variant	1/15	1		A2	P15391-2
RABEP2	ENST00000566762.1 linkuse as main transcript	c.-150+4179C>G		intron_variant		4
CD19	ENST00000565089.5 linkuse as main transcript	n.121G>C		non_coding_transcript_exon_variant	1/13	2

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152186

Hom.:

Cov.:

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:

0.000414

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000676

AC:

AN:

251484

Hom.:

AF XY:

0.0000736

AC XY:

AN XY:

135920

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 SAS exome

AF:

0.000555

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000253

AC:

AN:

1461096

Hom.:

Cov.:

AF XY:

0.0000316

AC XY:

AN XY:

726908

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.000429

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152304

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74470

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000414

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ExAC

AF:

0.0000741

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Immunodeficiency, common variable, 3

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Neuberg Centre For Genomic Medicine, NCGM

May 20, 2023

The missense c.706G>C (p.Ala236Pro) variant in the CD19 gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. This variant is absent in the gnomAD Exomes and novel in 1000 Genomes. The amino acid Alanine at position 236 is changed to a Proline changing protein sequence and it might alter its composition and physico-chemical properties. Multiple lines of computational evidence (Polyphen - Benign, SIFT - Tolerated and MutationTaster - Polymorphism) predict conflicting damaging effect on protein structure and function for this variant. The amino acid change p.Ala236Pro in CD19 is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.15

BayesDel_addAF

Benign

-0.56

BayesDel_noAF

Benign

-0.69

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.50

.;T;.

Eigen

Benign

0.11

Eigen_PC

Benign

0.14

FATHMM_MKL

Benign

0.36

LIST_S2

Benign

0.51

T;T;.

M_CAP

Benign

0.010

MetaRNN

Benign

0.12

T;T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

1.2

L;L;L

MutationTaster

Benign

0.87

N;N;N

PrimateAI

Benign

0.24

PROVEAN

Benign

-1.6

N;N;N

REVEL

Benign

0.052

Sift

Benign

0.13

T;T;T

Sift4G

Benign

0.15

T;T;T

Polyphen

0.95

.;P;.

Vest4

0.17

MutPred

0.27

Loss of ubiquitination at K27 (P = 0.0839);Loss of ubiquitination at K27 (P = 0.0839);Loss of ubiquitination at K27 (P = 0.0839);

MVP

0.50

MPC

0.87

ClinPred

0.19

GERP RS

4.3

Varity_R

0.23

gMVP

0.53

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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