rs879254354

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_006218.4(PIK3CA):​c.2016-3T>C variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000814 in 1,596,608 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000083 ( 0 hom. )

Consequence

PIK3CA
NM_006218.4 splice_region, intron

Scores

2
Splicing: ADA: 0.0001924
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.575

Publications

0 publications found
Variant links:
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: Ambry Genetics, Labcorp Genetics (formerly Invitae), 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)
  • familial ovarian cancer
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
  • hereditary breast carcinoma
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.34).
BS2
High AC in GnomAdExome4 at 12 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PIK3CANM_006218.4 linkc.2016-3T>C splice_region_variant, intron_variant Intron 13 of 20 ENST00000263967.4 NP_006209.2 P42336Q4LE51
PIK3CAXM_006713658.5 linkc.2016-3T>C splice_region_variant, intron_variant Intron 13 of 20 XP_006713721.1 P42336Q4LE51

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PIK3CAENST00000263967.4 linkc.2016-3T>C splice_region_variant, intron_variant Intron 13 of 20 2 NM_006218.4 ENSP00000263967.3 P42336

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152206
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000125
AC:
3
AN:
239054
AF XY:
0.0000154
show subpopulations
Gnomad AFR exome
AF:
0.000131
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000911
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000831
AC:
12
AN:
1444402
Hom.:
0
Cov.:
29
AF XY:
0.00000418
AC XY:
3
AN XY:
718272
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32564
American (AMR)
AF:
0.00
AC:
0
AN:
41738
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25414
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39512
South Asian (SAS)
AF:
0.0000121
AC:
1
AN:
82714
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52866
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5666
European-Non Finnish (NFE)
AF:
0.00000996
AC:
11
AN:
1104340
Other (OTH)
AF:
0.00
AC:
0
AN:
59588
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.513
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152206
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74354
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41458
American (AMR)
AF:
0.00
AC:
0
AN:
15266
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68044
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Cowden syndrome Uncertain:1
Feb 18, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is present in population databases (no rsID available, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with PIK3CA-related conditions. This sequence change falls in intron 13 of the PIK3CA gene. It does not directly change the encoded amino acid sequence of the PIK3CA protein. It affects a nucleotide within the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 246682). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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
BayesDel_noAF
Benign
-0.34
CADD
Benign
6.5
DANN
Benign
0.93
PhyloP100
0.57

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00019
dbscSNV1_RF
Benign
0.0080
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: rs879254354; hg19: chr3-178938771; API