3-179203760-G-T

Position:

• chr3-179203760-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PM5 PP2

The NM_006218.4(PIK3CA):​c.1030G>T​(p.Val344Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V344M) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PIK3CA NM_006218.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.45

Genes affected

PIK3CA (HGNC:8975): (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha) Phosphatidylinositol 3-kinase is composed of an 85 kDa regulatory subunit and a 110 kDa catalytic subunit. The protein encoded by this gene represents the catalytic subunit, which uses ATP to phosphorylate PtdIns, PtdIns4P and PtdIns(4,5)P2. This gene has been found to be oncogenic and has been implicated in cervical cancers. A pseudogene of this gene has been defined on chromosome 22. [provided by RefSeq, Apr 2016]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a domain C2 PI3K-type (size 157) in uniprot entity PK3CA_HUMAN there are 6 pathogenic changes around while only 1 benign (86%) in NM_006218.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr3-179203760-G-A is described in Lovd as [Pathogenic].
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), PIK3CA. . Gene score misZ 5.5986 (greater than the threshold 3.09). Trascript score misZ 6.1406 (greater than threshold 3.09). GenCC has associacion of gene with hereditary breast carcinoma, vascular malformation, Cowden disease, Cowden syndrome 5, CLOVES syndrome, familial ovarian cancer, megalencephaly-capillary malformation-polymicrogyria syndrome, overgrowth syndrome and/or cerebral malformations due to abnormalities in MTOR pathway genes.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PIK3CA	NM_006218.4	c.1030G>T	p.Val344Leu	missense_variant	5/21	ENST00000263967.4	NP_006209.2
PIK3CA	XM_006713658.5	c.1030G>T	p.Val344Leu	missense_variant	5/21		XP_006713721.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PIK3CA	ENST00000263967.4	c.1030G>T	p.Val344Leu	missense_variant	5/21	2	NM_006218.4	ENSP00000263967	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	0.0
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.27	T;.
Eigen	Benign	0.18
Eigen_PC	Uncertain	0.34
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;D
M_CAP	Benign	0.064	D
MetaRNN	Uncertain	0.45	T;T
MetaSVM	Benign	-0.82	T
MutationAssessor	Benign	1.1	L;.
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.90	D
PROVEAN	Benign	-0.24	N;.
REVEL	Benign	0.29
Sift	Benign	0.039	D;.
Sift4G	Benign	0.43	T;.
Polyphen		0.64	P;.
Vest4		0.66
MutPred		0.32		Loss of MoRF binding (P = 0.1273);Loss of MoRF binding (P = 0.1273);
MVP		0.82
MPC		1.4
ClinPred		0.91	D
GERP RS		5.4
Varity_R		0.37
gMVP		0.73

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs1057519942; hg19: chr3-178921548;