20-23635344-G-C

Position:

chr20-23635344-G-C

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_000099.4(CST3):c.267C>G(p.Phe89Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000947 in 1,584,470 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000023 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

CST3
NM_000099.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.233

Variant links:

Genes affected

CST3 (HGNC:2475): (cystatin C) The cystatin superfamily encompasses proteins that contain multiple cystatin-like sequences. Some of the members are active cysteine protease inhibitors, while others have lost or perhaps never acquired this inhibitory activity. There are three inhibitory families in the superfamily, including the type 1 cystatins (stefins), type 2 cystatins and the kininogens. The type 2 cystatin proteins are a class of cysteine proteinase inhibitors found in a variety of human fluids and secretions, where they appear to provide protective functions. The cystatin locus on chromosome 20 contains the majority of the type 2 cystatin genes and pseudogenes. This gene is located in the cystatin locus and encodes the most abundant extracellular inhibitor of cysteine proteases, which is found in high concentrations in biological fluids and is expressed in virtually all organs of the body. A mutation in this gene has been associated with amyloid angiopathy. Expression of this protein in vascular wall smooth muscle cells is severely reduced in both atherosclerotic and aneurysmal aortic lesions, establishing its role in vascular disease. In addition, this protein has been shown to have an antimicrobial function, inhibiting the replication of herpes simplex virus. Alternative splicing results in multiple transcript variants encoding a single protein. [provided by RefSeq, Nov 2014]

CST3 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.18958056).

BS2

High AC in GnomAdExome4 at 12 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CST3	NM_000099.4 linkuse as main transcript	c.267C>G	p.Phe89Leu	missense_variant	2/3	ENST00000376925.8	NP_000090.1
CST3	NM_001288614.2 linkuse as main transcript	c.267C>G	p.Phe89Leu	missense_variant	2/4		NP_001275543.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris
CST3	ENST00000376925.8 linkuse as main transcript	c.267C>G	p.Phe89Leu	missense_variant	2/3	1	NM_000099.4	ENSP00000366124	P1
CST3	ENST00000398411.5 linkuse as main transcript	c.267C>G	p.Phe89Leu	missense_variant	2/4	1		ENSP00000381448	P1
CST3	ENST00000398409.1 linkuse as main transcript	c.267C>G	p.Phe89Leu	missense_variant	3/4	3		ENSP00000381446	P1

Frequencies

GnomAD3 genomes

AF:

0.0000235

AC:

AN:

127746

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000890

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

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251012

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135706

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.00000824

AC:

AN:

1456724

Hom.:

Cov.:

AF XY:

0.00000414

AC XY:

AN XY:

724674

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000226

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.000183

GnomAD4 genome

AF:

0.0000235

AC:

AN:

127746

Hom.:

Cov.:

AF XY:

0.0000479

AC XY:

AN XY:

62606

show subpopulations

Gnomad4 AFR

AF:

0.0000890

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 24, 2023

This sequence change replaces phenylalanine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 89 of the CST3 protein (p.Phe89Leu). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with CST3-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The leucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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

AlphaMissense

Pathogenic

0.94

BayesDel_addAF

Benign

-0.20

BayesDel_noAF

Benign

-0.52

CADD

Benign

DANN

Benign

0.88

DEOGEN2

Benign

0.26

T;T;T

Eigen

Benign

-0.94

Eigen_PC

Benign

-1.0

FATHMM_MKL

Benign

0.068

LIST_S2

Benign

0.48

.;.;T

M_CAP

Benign

0.0034

MetaRNN

Benign

0.19

T;T;T

MetaSVM

Benign

-1.0

MutationAssessor

Benign

0.78

N;N;N

MutationTaster

Benign

1.0

N;N;N

PrimateAI

Uncertain

0.65

PROVEAN

Uncertain

-3.0

D;D;D

REVEL

Benign

0.036

Sift

Benign

0.18

T;T;T

Sift4G

Benign

0.10

T;T;T

Polyphen

0.43

B;B;B

Vest4

0.23

MutPred

0.54

Loss of catalytic residue at F89 (P = 0.1139);Loss of catalytic residue at F89 (P = 0.1139);Loss of catalytic residue at F89 (P = 0.1139);

MVP

0.19

MPC

0.52

ClinPred

0.15

GERP RS

0.22

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.52

gMVP

0.47

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over