chr20-8658556-A-C

Position:

• chr20-8658556-A-C

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 2P and 10B. PM2 BP4_Strong BP6 BP7 BS1

The NM_015192.4(PLCB1):​c.714A>C​(p.Pro238Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000355 in 1,606,526 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.00021 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00037 (0 hom.)
• Consequence: PLCB1 NM_015192.4 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:2
• Conservation: PhyloP100: 0.629

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]

PLCB1 (HGNC:):

ACMG classification

Verdict is Benign. Variant got -8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.53).
• BP6: Variant 20-8658556-A-C is Benign according to our data. Variant chr20-8658556-A-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 339499.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=2}.
• BP7: Synonymous conserved (PhyloP=0.629 with no splicing effect.
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00021 (32/152186) while in subpopulation NFE AF= 0.000367 (25/68028). AF 95% confidence interval is 0.000255. There are 0 homozygotes in gnomad4. There are 17 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PLCB1	NM_015192.4	c.714A>C	p.Pro238Pro	synonymous_variant	9/32	ENST00000338037.11	NP_056007.1
PLCB1	NM_182734.3	c.714A>C	p.Pro238Pro	synonymous_variant	9/33		NP_877398.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PLCB1	ENST00000338037.11	c.714A>C	p.Pro238Pro	synonymous_variant	9/32	1	NM_015192.4	ENSP00000338185.6

Frequencies

GnomAD3 genomes AF: 0.000210 AC: 32 AN: 152186 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000145

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000367

Gnomad OTH AF: 0.000478

GnomAD3 exomes AF: 0.000111 AC: 27 AN: 243628 Hom.: 0 AF XY: 0.000129 AC XY: 17 AN XY: 131562

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000304

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: 0.000234

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000371 AC: 539 AN: 1454340 Hom.: 0 Cov.: 30 AF XY: 0.000358 AC XY: 259 AN XY: 723206

Gnomad4 AFR exome AF: 0.0000609

Gnomad4 AMR exome AF: 0.0000466

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000118

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.000470

Gnomad4 OTH exome AF: 0.000216

GnomAD4 genome AF: 0.000210 AC: 32 AN: 152186 Hom.: 0 Cov.: 32 AF XY: 0.000229 AC XY: 17 AN XY: 74342

Gnomad4 AFR AF: 0.000145

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000367

Gnomad4 OTH AF: 0.000478

Alfa AF: 0.000155 Hom.: 0

Bravo AF: 0.000136

EpiCase AF: 0.000219

EpiControl AF: 0.000656

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:1 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Oct 01, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Jun 26, 2017	- -

Developmental and epileptic encephalopathy, 12 Uncertain:1 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 02, 2024	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.53
CADD	Benign	8.6
DANN	Benign	0.73
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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: rs147567110; hg19: chr20-8639203;