chr20-8790185-C-T

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_ModerateBS1_Supporting

The NM_015192.4(PLCB1):​c.3347C>T​(p.Ala1116Val) variant causes a missense change. The variant allele was found at a frequency of 0.000277 in 1,608,914 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A1116T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00016 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00029 ( 0 hom. )

Consequence

PLCB1
NM_015192.4 missense

Scores

3
4
12

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 6.94

Publications

3 publications found
Variant links:
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 Gene-Disease associations (from GenCC):
  • genetic developmental and epileptic encephalopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • developmental and epileptic encephalopathy, 12
    Inheritance: AR Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
  • infantile spasms
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • malignant migrating partial seizures of infancy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -3 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.23899156).
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000164 (25/152204) while in subpopulation NFE AF = 0.000279 (19/68006). AF 95% confidence interval is 0.000182. There are 0 homozygotes in GnomAd4. There are 12 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PLCB1NM_015192.4 linkc.3347C>T p.Ala1116Val missense_variant Exon 31 of 32 ENST00000338037.11 NP_056007.1 Q9NQ66-1
PLCB1NM_182734.3 linkc.3347C>T p.Ala1116Val missense_variant Exon 31 of 33 NP_877398.1 Q9NQ66-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PLCB1ENST00000338037.11 linkc.3347C>T p.Ala1116Val missense_variant Exon 31 of 32 1 NM_015192.4 ENSP00000338185.6 Q9NQ66-1

Frequencies

GnomAD3 genomes
AF:
0.000164
AC:
25
AN:
152086
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000966
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000279
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000263
AC:
65
AN:
247298
AF XY:
0.000299
show subpopulations
Gnomad AFR exome
AF:
0.000125
Gnomad AMR exome
AF:
0.0000873
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000464
Gnomad NFE exome
AF:
0.000342
Gnomad OTH exome
AF:
0.000330
GnomAD4 exome
AF:
0.000288
AC:
420
AN:
1456710
Hom.:
0
Cov.:
31
AF XY:
0.000286
AC XY:
207
AN XY:
724580
show subpopulations
African (AFR)
AF:
0.0000602
AC:
2
AN:
33248
American (AMR)
AF:
0.000135
AC:
6
AN:
44594
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26074
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39502
South Asian (SAS)
AF:
0.000420
AC:
36
AN:
85710
European-Finnish (FIN)
AF:
0.0000375
AC:
2
AN:
53288
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5758
European-Non Finnish (NFE)
AF:
0.000318
AC:
353
AN:
1108428
Other (OTH)
AF:
0.000349
AC:
21
AN:
60108
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.447
Heterozygous variant carriers
0
18
36
54
72
90
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000164
AC:
25
AN:
152204
Hom.:
0
Cov.:
33
AF XY:
0.000161
AC XY:
12
AN XY:
74424
show subpopulations
African (AFR)
AF:
0.0000963
AC:
4
AN:
41522
American (AMR)
AF:
0.0000655
AC:
1
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10590
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000279
AC:
19
AN:
68006
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.531
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000268
Hom.:
0
Bravo
AF:
0.000200
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000465
AC:
4
ExAC
AF:
0.000288
AC:
35
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
May 16, 2023
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

BP4, PP2 -

Mar 25, 2022
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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 -

Developmental and epileptic encephalopathy, 12 Uncertain:1
Jan 25, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 1116 of the PLCB1 protein (p.Ala1116Val). This variant is present in population databases (rs148936543, gnomAD 0.06%). This variant has not been reported in the literature in individuals affected with PLCB1-related conditions. ClinVar contains an entry for this variant (Variation ID: 570898). 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 PLCB1 protein function with a negative predictive value of 80%. 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
0.14
BayesDel_addAF
Benign
-0.20
T
BayesDel_noAF
Benign
-0.17
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.28
.;.;T;.;.;T;T
Eigen
Pathogenic
0.69
Eigen_PC
Pathogenic
0.73
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.97
D;.;D;D;D;D;D
M_CAP
Benign
0.022
T
MetaRNN
Benign
0.24
T;T;T;T;T;T;T
MetaSVM
Benign
-0.87
T
MutationAssessor
Uncertain
2.3
.;M;M;M;.;.;.
PhyloP100
6.9
PrimateAI
Uncertain
0.78
T
PROVEAN
Benign
-1.2
.;N;N;N;.;.;.
REVEL
Benign
0.22
Sift
Benign
0.21
.;T;T;T;.;.;.
Sift4G
Benign
0.27
.;T;T;T;T;T;D
Polyphen
0.99, 1.0
.;D;D;D;.;.;.
Vest4
0.66, 0.63, 0.66
MVP
0.46
MPC
0.67
ClinPred
0.56
D
GERP RS
6.0
PromoterAI
-0.0037
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.10
gMVP
0.11
Mutation Taster
=84/16
polymorphism

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

Other links and lift over

dbSNP: rs148936543; hg19: chr20-8770832; COSMIC: COSV62065211; COSMIC: COSV62065211; API