10-96196964-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_013314.4(BLNK):c.1195C>T(p.Arg399Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000411 in 1,461,096 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 (★). Synonymous variant affecting the same amino acid position (i.e. R399R) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: BLNK NM_013314.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.950

Genes affected

BLNK (HGNC:14211): (B cell linker) This gene encodes a cytoplasmic linker or adaptor protein that plays a critical role in B cell development. This protein bridges B cell receptor-associated kinase activation with downstream signaling pathways, thereby affecting various biological functions. The phosphorylation of five tyrosine residues is necessary for this protein to nucleate distinct signaling effectors following B cell receptor activation. Mutations in this gene cause hypoglobulinemia and absent B cells, a disease in which the pro- to pre-B-cell transition is developmentally blocked. Deficiency in this protein has also been shown in some cases of pre-B acute lymphoblastic leukemia. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, May 2012]

ZNF518A (HGNC:29009): (zinc finger protein 518A) The protein encoded by this gene is a member of the krueppel C2H2-type zinc finger protein family. The encoded protein contains five zinc fingers and is likely a nuclear transcriptional regulator. Numerous transcript variants encoding two different isoforms have been found for this gene. [provided by RefSeq, Aug 2016]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.128 CDS is truncated, and there are 1 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 10-96196964-G-A is Pathogenic according to our data. Variant chr10-96196964-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 1072783.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BLNK	NM_013314.4	c.1195C>T	p.Arg399Ter	stop_gained	16/17	ENST00000224337.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BLNK	ENST00000224337.10	c.1195C>T	p.Arg399Ter	stop_gained	16/17	1	NM_013314.4	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251184 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135794

Gnomad AFR exome AF: 0.0000616

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: 0.000163

GnomAD4 exome AF: 0.00000411 AC: 6 AN: 1461096 Hom.: 0 Cov.: 31 AF XY: 0.00000688 AC XY: 5 AN XY: 726902

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: 0.00000270

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Agammaglobulinemia 4, autosomal recessive Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Feb 20, 2023

This sequence change creates a premature translational stop signal (p.Arg399*) in the BLNK gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in BLNK are known to be pathogenic (PMID: 10583958, 24582315). This variant is present in population databases (no rsID available, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with BLNK-related conditions. ClinVar contains an entry for this variant (Variation ID: 1072783). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.59
Cadd	Pathogenic	36
Dann	Uncertain	1.0
Eigen	Uncertain	0.52
Eigen_PC	Uncertain	0.34
FATHMM_MKL	Uncertain	0.90	D
MutationTaster	Benign	1.0	A;A;D;D
Vest4		0.93
GERP RS		2.1

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

LitVar

Other links and lift over

dbSNP: rs1554894837; hg19: chr10-97956720; COSMIC: COSV104553154; COSMIC: COSV104553154;