12-18282302-C-T

Position:

• chr12-18282302-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_001288772.2(PIK3C2G):​c.221C>T​(p.Thr74Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PIK3C2G NM_001288772.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.190

Genes affected

PIK3C2G (HGNC:8973): (phosphatidylinositol-4-phosphate 3-kinase catalytic subunit type 2 gamma) The protein encoded by this gene belongs to the phosphoinositide 3-kinase (PI3K) family. PI3-kinases play roles in signaling pathways involved in cell proliferation, oncogenic transformation, cell survival, cell migration, and intracellular protein trafficking. This protein contains a lipid kinase catalytic domain as well as a C-terminal C2 domain, a characteristic of class II PI3-kinases. C2 domains act as calcium-dependent phospholipid binding motifs that mediate translocation of proteins to membranes, and may also mediate protein-protein interactions. This gene may play a role in several diseases, including type II diabetes. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2014]

PIK3C2G (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.054419994).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PIK3C2G	NM_001288772.2	c.221C>T	p.Thr74Ile	missense_variant	2/33	ENST00000538779.6	NP_001275701.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PIK3C2G	ENST00000538779.6	c.221C>T	p.Thr74Ile	missense_variant	2/33	5	NM_001288772.2	ENSP00000445381.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 21, 2024

The c.221C>T (p.T74I) alteration is located in exon 2 (coding exon 1) of the PIK3C2G gene. This alteration results from a C to T substitution at nucleotide position 221, causing the threonine (T) at amino acid position 74 to be replaced by an isoleucine (I). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.084
BayesDel_addAF	Benign	-0.29	T
BayesDel_noAF	Benign	-0.66
CADD	Benign	0.14
DANN	Benign	0.94
DEOGEN2	Benign	0.0099	T;.;T;T
Eigen	Benign	-1.5
Eigen_PC	Benign	-1.5
FATHMM_MKL	Benign	0.014	N
LIST_S2	Benign	0.56	T;T;T;.
M_CAP	Benign	0.023	T
MetaRNN	Benign	0.054	T;T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.0	.;.;N;N
PrimateAI	Benign	0.22	T
PROVEAN	Benign	-1.0	N;N;N;N
REVEL	Benign	0.055
Sift	Uncertain	0.0070	D;D;D;D
Sift4G	Uncertain	0.019	D;D;D;D
Polyphen		0.053, 0.031	.;B;B;B
Vest4		0.094
MutPred		0.35		Gain of catalytic residue at T74 (P = 4e-04);Gain of catalytic residue at T74 (P = 4e-04);Gain of catalytic residue at T74 (P = 4e-04);Gain of catalytic residue at T74 (P = 4e-04);
MVP		0.29
MPC		0.013
ClinPred		0.19	T
GERP RS		-3.5
Varity_R		0.043
gMVP		0.084

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: rs1949254154; hg19: chr12-18435236;