rs128621200

Positions:

• chrX-101356102-A-G

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.1516T>C​(p.Cys506Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000000911 in 1,098,261 control chromosomes in the GnomAD database, with no homozygous occurrence. There are no hemizygote samples in GnomAD. 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. C506Y) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 23)
  • Exomes 𝑓: 9.1e-7 (0 hom. 0 hem.)
• Consequence: BTK NM_000061.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter P:1 U:1
• Conservation: PhyloP100: 3.82

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 helix (size 19) in uniprot entity BTK_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) 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 gene, where missense usually causes diseases (based on misZ statistic), BTK. . Gene score misZ 4.0394 (greater than the threshold 3.09). GenCC has associacion of gene with 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, 0.981

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BTK	NM_000061.3	c.1516T>C	p.Cys506Arg	missense_variant	15/19	ENST00000308731.8	NP_000052.1
BTK	NM_001287344.2	c.1618T>C	p.Cys540Arg	missense_variant	15/19		NP_001274273.1
BTK	NM_001287345.2	c.1039-1408T>C		intron_variant			NP_001274274.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BTK	ENST00000308731.8	c.1516T>C	p.Cys506Arg	missense_variant	15/19	1	NM_000061.3	ENSP00000308176	P3

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome AF: 9.11e-7 AC: 1 AN: 1098261 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 363615

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000119

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 23

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

X-linked agammaglobulinemia Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Oct 01, 1994

- -

X-linked agammaglobulinemia with growth hormone deficiency Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 16, 2019

This sequence change replaces cysteine with arginine at codon 506 of the BTK protein (p.Cys506Arg). The cysteine residue is moderately conserved and there is a large physicochemical difference between cysteine and arginine. This variant is not present in population databases (ExAC no frequency). This variant has been observed in an individual affected with X-linked agammaglobulinemia (PMID: 7880320). ClinVar contains an entry for this variant (Variation ID: 11376). 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: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C15"). This variant disrupts the p.Cys506 amino acid residue in BTK. Other variant(s) that disrupt this residue have been observed in individuals with BTK-related conditions (PMID: 15661032, 9143921, 9445504, 10859027), suggesting that it is a clinically significant residue. As a result, variants that disrupt this residue are likely to be causative of disease. 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	1.0
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.48
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D;.;D
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.96	D;D;D
M_CAP	Pathogenic	0.76	D
MetaRNN	Pathogenic	0.98	D;D;D
MetaSVM	Uncertain	-0.16	T
MutationAssessor	Uncertain	2.8	.;.;M
MutationTaster	Benign	1.0	A;A
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-9.5	.;.;D
REVEL	Pathogenic	0.85
Sift	Uncertain	0.0010	.;.;D
Sift4G	Uncertain	0.0020	D;D;D
Polyphen		1.0	.;.;D
Vest4		0.97
MutPred		0.81		Gain of disorder (P = 0.0391);.;Gain of disorder (P = 0.0391);
MVP		1.0
MPC		3.4
ClinPred		1.0	D
GERP RS		5.5
Varity_R		1.0
gMVP		1.0

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

Other links and lift over

dbSNP: rs128621200; hg19: chrX-100611090;