chr20-23750815-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_001898.3(CST1):​c.52G>A​(p.Ala18Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,914 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

CST1
NM_001898.3 missense

Scores

19

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.500
Variant links:
Genes affected
CST1 (HGNC:2473): (cystatin SN) 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 a cysteine proteinase inhibitor found in saliva, tears, urine, and seminal fluid. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.079663366).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CST1NM_001898.3 linkuse as main transcriptc.52G>A p.Ala18Thr missense_variant 1/3 ENST00000304749.7 NP_001889.2 P01037

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CST1ENST00000304749.7 linkuse as main transcriptc.52G>A p.Ala18Thr missense_variant 1/31 NM_001898.3 ENSP00000305731.2 P01037
CST1ENST00000398402.1 linkuse as main transcriptc.52G>A p.Ala18Thr missense_variant 2/45 ENSP00000381439.1 P01037

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152152
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.00000797
AC:
2
AN:
250974
Hom.:
0
AF XY:
0.00000737
AC XY:
1
AN XY:
135642
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
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:
0.00000881
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461762
Hom.:
0
Cov.:
36
AF XY:
0.00000275
AC XY:
2
AN XY:
727166
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.0000224
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:
8.99e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152152
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74322
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000655
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:
0.0000113
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsDec 28, 2022The c.52G>A (p.A18T) alteration is located in exon 1 (coding exon 1) of the CST1 gene. This alteration results from a G to A substitution at nucleotide position 52, causing the alanine (A) at amino acid position 18 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.081
BayesDel_addAF
Benign
-0.38
T
BayesDel_noAF
Benign
-0.70
CADD
Benign
0.36
DANN
Benign
0.61
DEOGEN2
Benign
0.043
T;T
Eigen
Benign
-1.6
Eigen_PC
Benign
-1.6
FATHMM_MKL
Benign
0.0069
N
LIST_S2
Benign
0.42
.;T
M_CAP
Benign
0.0012
T
MetaRNN
Benign
0.080
T;T
MetaSVM
Benign
-0.98
T
MutationAssessor
Benign
1.7
L;L
MutationTaster
Benign
1.0
N;N
PrimateAI
Benign
0.48
T
PROVEAN
Benign
-1.7
N;N
REVEL
Benign
0.017
Sift
Benign
0.097
T;T
Sift4G
Benign
0.22
T;T
Polyphen
0.0050
B;B
Vest4
0.046
MutPred
0.47
Loss of helix (P = 0.028);Loss of helix (P = 0.028);
MVP
0.040
MPC
0.0035
ClinPred
0.028
T
GERP RS
-0.99
Varity_R
0.044
gMVP
0.24

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.

Other links and lift over

dbSNP: rs760570692; hg19: chr20-23731452; API