3-179204486-C-G

Variant names:

• chr3-179204486-C-G
• rs2699896
• NM_006218.4:c.1060-17C>G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_006218.4(PIK3CA):​c.1060-17C>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000658 in 151,988 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. There are indicators that this mutation may affect the branch point.. The gene PIK3CA is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 31)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PIK3CA NM_006218.4 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.523
• Publications: 24 publications found

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]

PIK3CA Gene-Disease associations (from GenCC):

• overgrowth syndrome and/or cerebral malformations due to abnormalities in MTOR pathway genes

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• megalencephaly-capillary malformation-polymicrogyria syndrome

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
• vascular malformation

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• Cowden disease

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Cowden syndrome 5

  Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
• hereditary breast carcinoma

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• familial ovarian cancer

  Inheritance: Unknown Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Specifications for PIK3CA are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: This position, referring to a specific DNA site, is a probable branch point but rather VUS (scored 4 / 10). The score ranges from 0 to 10, with values ≤3 considered benign and >5 classified as pathogenic. Computational evidence support a benign effect (BayesDel_noAF=-0.84).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006218.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PIK3CA	NM_006218.4	MANE Select	c.1060-17C>G		intron	N/A	NP_006209.2	P42336

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PIK3CA	ENST00000263967.4	TSL:2 MANE Select	c.1060-17C>G		intron	N/A	ENSP00000263967.3	P42336
	PIK3CA	ENST00000955190.1		c.1090-17C>G		intron	N/A	ENSP00000625249.1
	PIK3CA	ENST00000876545.1		c.1060-17C>G		intron	N/A	ENSP00000546604.1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 151988 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1142084 Hom.: 0 Cov.: 15 AF XY: 0.00 AC XY: 0 AN XY: 583008

African (AFR) AF: 0.00 AC: 0 AN: 27152

American (AMR) AF: 0.00 AC: 0 AN: 43830

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 23908

East Asian (EAS) AF: 0.00 AC: 0 AN: 38078

South Asian (SAS) AF: 0.00 AC: 0 AN: 78956

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53010

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5128

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 822434

Other (OTH) AF: 0.00 AC: 0 AN: 49588

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 151988 Hom.: 0 Cov.: 31 AF XY: 0.0000135 AC XY: 1 AN XY: 74210

African (AFR) AF: 0.00 AC: 0 AN: 41410

American (AMR) AF: 0.00 AC: 0 AN: 15256

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5182

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10528

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67992

Other (OTH) AF: 0.00 AC: 0 AN: 2094

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.84
CADD	Benign	0.53
DANN	Benign	0.17
PhyloP100		-0.52
BranchPoint Hunter		4.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs2699896; hg19: chr3-178922274;