rs1555383695

Positions:

• chr14-104775098-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_001382430.1(AKT1):​c.545A>G​(p.Lys182Arg) 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. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: AKT1 NM_001382430.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.75

Genes affected

AKT1 (HGNC:391): (AKT serine/threonine kinase 1) This gene encodes one of the three members of the human AKT serine-threonine protein kinase family which are often referred to as protein kinase B alpha, beta, and gamma. These highly similar AKT proteins all have an N-terminal pleckstrin homology domain, a serine/threonine-specific kinase domain and a C-terminal regulatory domain. These proteins are phosphorylated by phosphoinositide 3-kinase (PI3K). AKT/PI3K forms a key component of many signalling pathways that involve the binding of membrane-bound ligands such as receptor tyrosine kinases, G-protein coupled receptors, and integrin-linked kinase. These AKT proteins therefore regulate a wide variety of cellular functions including cell proliferation, survival, metabolism, and angiogenesis in both normal and malignant cells. AKT proteins are recruited to the cell membrane by phosphatidylinositol 3,4,5-trisphosphate (PIP3) after phosphorylation of phosphatidylinositol 4,5-bisphosphate (PIP2) by PI3K. Subsequent phosphorylation of both threonine residue 308 and serine residue 473 is required for full activation of the AKT1 protein encoded by this gene. Phosphorylation of additional residues also occurs, for example, in response to insulin growth factor-1 and epidermal growth factor. Protein phosphatases act as negative regulators of AKT proteins by dephosphorylating AKT or PIP3. The PI3K/AKT signalling pathway is crucial for tumor cell survival. Survival factors can suppress apoptosis in a transcription-independent manner by activating AKT1 which then phosphorylates and inactivates components of the apoptotic machinery. AKT proteins also participate in the mammalian target of rapamycin (mTOR) signalling pathway which controls the assembly of the eukaryotic translation initiation factor 4F (eIF4E) complex and this pathway, in addition to responding to extracellular signals from growth factors and cytokines, is disregulated in many cancers. Mutations in this gene are associated with multiple types of cancer and excessive tissue growth including Proteus syndrome and Cowden syndrome 6, and breast, colorectal, and ovarian cancers. Multiple alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Jul 2020]

AKT1 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), AKT1. . Gene score misZ 3.4778 (greater than the threshold 3.09). Trascript score misZ 4.2155 (greater than threshold 3.09). GenCC has associacion of gene with Proteus syndrome, Cowden disease, Cowden syndrome 6.
• BP4: Computational evidence support a benign effect (MetaRNN=0.3420527).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
AKT1	NM_001382430.1	c.545A>G	p.Lys182Arg	missense_variant	7/15	ENST00000649815.2	NP_001369359.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
AKT1	ENST00000649815.2	c.545A>G	p.Lys182Arg	missense_variant	7/15		NM_001382430.1	ENSP00000497822.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cowden syndrome 6 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 15, 2017

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. Experimental studies in tissue culture have shown that this missense change does not impact the ability of AKT1 to phosphorylate GSK3beta (PMID: 23884910). This variant has not been reported in the literature in individuals with AKT1-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces lysine with arginine at codon 182 of the AKT1 protein (p.Lys182Arg). The lysine residue is moderately conserved and there is a small physicochemical difference between lysine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.090
BayesDel_addAF	Benign	-0.0054	T
BayesDel_noAF	Benign	-0.25
CADD	Benign	21
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.43	T;T;T;T;T;T;T
Eigen	Benign	-0.42
Eigen_PC	Benign	-0.28
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Benign	0.69	.;.;.;.;.;.;T
M_CAP	Uncertain	0.21	D
MetaRNN	Benign	0.34	T;T;T;T;T;T;T
MetaSVM	Benign	-0.96	T
MutationAssessor	Benign	1.5	L;L;L;L;L;L;L
PrimateAI	Pathogenic	0.82	D
PROVEAN	Benign	-1.8	N;N;N;N;N;.;N
REVEL	Benign	0.25
Sift	Benign	0.32	T;T;T;T;T;.;T
Sift4G	Benign	0.45	T;T;T;T;T;.;T
Polyphen		0.028	B;B;B;B;B;B;B
Vest4		0.23
MutPred		0.53		Loss of methylation at K182 (P = 0.0401);Loss of methylation at K182 (P = 0.0401);Loss of methylation at K182 (P = 0.0401);Loss of methylation at K182 (P = 0.0401);Loss of methylation at K182 (P = 0.0401);Loss of methylation at K182 (P = 0.0401);Loss of methylation at K182 (P = 0.0401);
MVP		0.65
MPC		1.5
ClinPred		0.58	D
GERP RS		3.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.30
gMVP		0.74

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: rs1555383695; hg19: chr14-105241435;