X-101349943-C-A

Variant names:

• chrX-101349943-C-A
• NM_000061.3:c.1922G>T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM1 PM2 PM5 PP2 PP3_Strong

The NM_000061.3(BTK):​c.1922G>T​(p.Arg641Leu) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R641C) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 22)
• Consequence: BTK NM_000061.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.65

Genes affected

BTK (HGNC:1133): (Bruton tyrosine kinase) The protein encoded by this gene plays a crucial role in B-cell development. Mutations in this gene cause X-linked agammaglobulinemia type 1, which is an immunodeficiency characterized by the failure to produce mature B lymphocytes, and associated with a failure of Ig heavy chain rearrangement. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Dec 2013]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PM1: In a domain Protein kinase (size 253) in uniprot entity BTK_HUMAN there are 43 pathogenic changes around while only 1 benign (98%) in NM_000061.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
• PP2: Missense variant in the BTK gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 90 curated pathogenic missense variants (we use a threshold of 10). The gene has 26 curated benign missense variants. Gene score misZ: 4.0394 (above the threshold of 3.09). GenCC associations: The gene is linked to short stature due to isolated growth hormone deficiency with X-linked hypogammaglobulinemia, Bruton-type agammaglobulinemia, isolated growth hormone deficiency type III.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BTK	NM_000061.3	c.1922G>T	p.Arg641Leu	missense_variant	Exon 19 of 19	ENST00000308731.8	NP_000052.1
BTK	NM_001287344.2	c.2024G>T	p.Arg675Leu	missense_variant	Exon 19 of 19		NP_001274273.1
BTK	NM_001287345.2	c.1394G>T	p.Arg465Leu	missense_variant	Exon 17 of 17		NP_001274274.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BTK	ENST00000308731.8	c.1922G>T	p.Arg641Leu	missense_variant	Exon 19 of 19	1	NM_000061.3	ENSP00000308176.8

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 22

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

X-linked agammaglobulinemia with growth hormone deficiency Uncertain:1

Aug 31, 2024

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 leucine, which is neutral and non-polar, at codon 641 of the BTK protein (p.Arg641Leu). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with agammaglobulinemia (internal data). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt BTK protein function with a positive predictive value of 80%. This variant disrupts the p.Arg641 amino acid residue in BTK. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 7633420, 17765309). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.71	D
BayesDel_noAF	Pathogenic	0.78
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	.;.;D
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.96	D;D;D
M_CAP	Pathogenic	0.70	D
MetaRNN	Pathogenic	0.99	D;D;D
MetaSVM	Pathogenic	0.86	D
MutationAssessor	Pathogenic	5.2	.;.;H
PrimateAI	Uncertain	0.55	T
PROVEAN	Pathogenic	-5.8	D;.;D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;.;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;.;D
Vest4		0.88
MutPred		0.95		.;.;Loss of disorder (P = 0.0519);
MVP		1.0
MPC		2.8
ClinPred		1.0	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.99
gMVP		1.0

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

No publications associated with this variant yet.

Other links and lift over

hg19: chrX-100604931;