10-96200149-C-T

Position:

• chr10-96200149-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BS1_Supporting

The NM_013314.4(BLNK):​c.1021G>A​(p.Val341Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000516 in 1,613,848 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.00039 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00053 (1 hom.)
• Consequence: BLNK NM_013314.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:1
• Conservation: PhyloP100: 0.621

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_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.013635129).
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.000388 (59/152110) while in subpopulation NFE AF= 0.000573 (39/68040). AF 95% confidence interval is 0.000431. There are 0 homozygotes in gnomad4. There are 33 alleles in male gnomad4 subpopulation. Median coverage is 32. 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
BLNK	NM_013314.4	c.1021G>A	p.Val341Ile	missense_variant	15/17	ENST00000224337.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BLNK	ENST00000224337.10	c.1021G>A	p.Val341Ile	missense_variant	15/17	1	NM_013314.4	P2

Frequencies

GnomAD3 genomes AF: 0.000388 AC: 59 AN: 152110 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000145

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00123

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000573

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000334 AC: 84 AN: 251274 Hom.: 0 AF XY: 0.000353 AC XY: 48 AN XY: 135804

Gnomad AFR exome AF: 0.000308

Gnomad AMR exome AF: 0.000116

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.000739

Gnomad NFE exome AF: 0.000484

Gnomad OTH exome AF: 0.000652

GnomAD4 exome AF: 0.000529 AC: 773 AN: 1461738 Hom.: 1 Cov.: 31 AF XY: 0.000510 AC XY: 371 AN XY: 727148

Gnomad4 AFR exome AF: 0.000119

Gnomad4 AMR exome AF: 0.0000894

Gnomad4 ASJ exome AF: 0.0000383

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.000468

Gnomad4 NFE exome AF: 0.000644

Gnomad4 OTH exome AF: 0.000331

GnomAD4 genome AF: 0.000388 AC: 59 AN: 152110 Hom.: 0 Cov.: 32 AF XY: 0.000444 AC XY: 33 AN XY: 74292

Gnomad4 AFR AF: 0.000145

Gnomad4 AMR AF: 0.0000655

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00123

Gnomad4 NFE AF: 0.000573

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000514 Hom.: 0

Bravo AF: 0.000264

TwinsUK AF: 0.000270 AC: 1

ALSPAC AF: 0.000259 AC: 1

ESP6500AA AF: 0.000454 AC: 2

ESP6500EA AF: 0.000581 AC: 5

ExAC AF: 0.000354 AC: 43

EpiCase AF: 0.000654

EpiControl AF: 0.000652

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:1 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Aug 30, 2022	In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Jul 01, 2024	BLNK: BP4 -

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 21, 2021

The c.1021G>A (p.V341I) alteration is located in exon 15 (coding exon 15) of the BLNK gene. This alteration results from a G to A substitution at nucleotide position 1021, causing the valine (V) at amino acid position 341 to be replaced by an isoleucine (I). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Agammaglobulinemia 4, autosomal recessive Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 27, 2022

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 341 of the BLNK protein (p.Val341Ile). This variant is present in population databases (rs144826995, gnomAD 0.07%). 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: 568111). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt BLNK protein function. 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	0.067
BayesDel_addAF	Benign	-0.45	T
BayesDel_noAF	Benign	-0.54
CADD	Benign	14
DANN	Benign	0.91
DEOGEN2	Benign	0.31	T;.;T;.
Eigen	Benign	-0.90
Eigen_PC	Benign	-0.90
FATHMM_MKL	Benign	0.075	N
LIST_S2	Benign	0.72	T;T;T;T
M_CAP	Benign	0.012	T
MetaRNN	Benign	0.014	T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	-0.19	N;.;.;N
MutationTaster	Benign	1.0	N;N;N;N
PrimateAI	Benign	0.34	T
PROVEAN	Benign	-0.15	N;N;.;N
REVEL	Benign	0.0070
Sift	Benign	0.22	T;T;.;T
Sift4G	Benign	0.57	T;T;T;T
Polyphen		0.0060	B;B;B;.
Vest4		0.10
MVP		0.39
MPC		0.26
ClinPred		0.0036	T
GERP RS		0.68
Varity_R		0.024
gMVP		0.21

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs144826995; hg19: chr10-97959905;