20-8132680-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_015192.4(PLCB1):c.29C>T(p.Ala10Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign 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. A10S) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PLCB1 NM_015192.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.72

Genes affected

PLCB1 (HGNC:15917): (phospholipase C beta 1) The protein encoded by this gene catalyzes the formation of inositol 1,4,5-trisphosphate and diacylglycerol from phosphatidylinositol 4,5-bisphosphate. This reaction uses calcium as a cofactor and plays an important role in the intracellular transduction of many extracellular signals. This gene is activated by two G-protein alpha subunits, alpha-q and alpha-11. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, PLCB1
• BP4: Computational evidence support a benign effect (MetaRNN=0.32478583).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PLCB1	NM_015192.4	c.29C>T	p.Ala10Val	missense_variant	1/32	ENST00000338037.11
PLCB1	NM_182734.3	c.29C>T	p.Ala10Val	missense_variant	1/33

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PLCB1	ENST00000338037.11	c.29C>T	p.Ala10Val	missense_variant	1/32	1	NM_015192.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Developmental and epileptic encephalopathy, 12 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 31, 2021

This sequence change replaces alanine with valine at codon 10 of the PLCB1 protein (p.Ala10Val). The alanine residue is weakly conserved and there is a small physicochemical difference between alanine and valine. This variant is not present in population databases (ExAC no frequency). 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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. This variant has not been reported in the literature in individuals affected with PLCB1-related conditions. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.44
BayesDel_addAF	Benign	-0.074	T
BayesDel_noAF	Benign	-0.34
Cadd	Pathogenic	26
Dann	Uncertain	1.0
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Uncertain	0.92	D
M_CAP	Uncertain	0.27	D
MetaRNN	Benign	0.32	T;T;T;T;T
MetaSVM	Benign	-0.73	T
MutationAssessor	Benign	1.9	L;L;.;.;L
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.87	D
PROVEAN	Benign	-1.0	N;N;.;.;N
REVEL	Benign	0.16
Sift	Benign	0.31	T;T;.;.;T
Sift4G	Benign	0.27	T;T;D;D;T
Polyphen		1.0	D;D;.;.;D
Vest4		0.48
MutPred		0.33		Gain of sheet (P = 0.0221);Gain of sheet (P = 0.0221);Gain of sheet (P = 0.0221);Gain of sheet (P = 0.0221);Gain of sheet (P = 0.0221);
MVP		0.33
MPC		0.10
ClinPred		0.98	D
GERP RS		4.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.26
gMVP		0.43

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: chr20-8113327;