chr16-81908453-G-T

Variant names:

• chr16-81908453-G-T
• rs370429726
• NM_002661.5:c.1595G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_002661.5(PLCG2):​c.1595G>T​(p.Trp532Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,836 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. W532C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PLCG2 NM_002661.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.54
• Publications: 0 publications found

Genes affected

PLCG2 (HGNC:9066): (phospholipase C gamma 2) The protein encoded by this gene is a transmembrane signaling enzyme that catalyzes the conversion of 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate to 1D-myo-inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG) using calcium as a cofactor. IP3 and DAG are second messenger molecules important for transmitting signals from growth factor receptors and immune system receptors across the cell membrane. Mutations in this gene have been found in autoinflammation, antibody deficiency, and immune dysregulation syndrome and familial cold autoinflammatory syndrome 3. [provided by RefSeq, Mar 2014]

PLCG2 Gene-Disease associations (from GenCC):

• autoinflammation-PLCG2-associated antibody deficiency-immune dysregulation

  Inheritance: AD Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet, G2P
• familial cold autoinflammatory syndrome 3

  Inheritance: AD Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.963

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002661.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PLCG2	NM_002661.5	MANE Select	c.1595G>T	p.Trp532Leu	missense	Exon 17 of 33	NP_002652.2
	PLCG2	NM_001425749.1		c.1595G>T	p.Trp532Leu	missense	Exon 18 of 34	NP_001412678.1
	PLCG2	NM_001425750.1		c.1595G>T	p.Trp532Leu	missense	Exon 17 of 33	NP_001412679.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PLCG2	ENST00000564138.6	TSL:1 MANE Select	c.1595G>T	p.Trp532Leu	missense	Exon 17 of 33	ENSP00000482457.1
	PLCG2	ENST00000567980.5	TSL:1	n.1839G>T		non_coding_transcript_exon	Exon 16 of 20
	PLCG2	ENST00000565054.7	TSL:5	c.1595G>T	p.Trp532Leu	missense	Exon 18 of 34	ENSP00000520638.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461836 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727222

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111978

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial cold autoinflammatory syndrome 3 Uncertain:1

Oct 29, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces tryptophan, which is neutral and slightly polar, with leucine, which is neutral and non-polar, at codon 532 of the PLCG2 protein (p.Trp532Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with PLCG2-related conditions. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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 v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.53
CADD	Pathogenic	27
DANN	Uncertain	0.98
DEOGEN2	Pathogenic	0.88	D
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.91	D
M_CAP	Pathogenic	0.54	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.9	H
PhyloP100		9.5
PrimateAI	Uncertain	0.70	T
PROVEAN	Pathogenic	-12	D
REVEL	Pathogenic	0.85
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.043	D
Polyphen		0.83	P
Vest4		0.72
MutPred		0.83		Loss of catalytic residue at W532 (P = 0.0032)
MVP		0.97
MPC		0.87
ClinPred		1.0	D
GERP RS		4.8
Varity_R		0.99
gMVP		0.75

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs370429726; hg19: chr16-81942058;