chr15-101177477-T-C

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_014918.5(CHSY1):​c.2320A>G​(p.Thr774Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,613,594 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T774S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

CHSY1
NM_014918.5 missense

Scores

2
17

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.74

Publications

0 publications found
Variant links:
Genes affected
CHSY1 (HGNC:17198): (chondroitin sulfate synthase 1) This gene encodes a member of the chondroitin N-acetylgalactosaminyltransferase family. These enzymes possess dual glucuronyltransferase and galactosaminyltransferase activity and play critical roles in the biosynthesis of chondroitin sulfate, a glycosaminoglycan involved in many biological processes including cell proliferation and morphogenesis. Decreased expression of this gene may play a role in colorectal cancer, and mutations in this gene are a cause of temtamy preaxial brachydactyly syndrome. [provided by RefSeq, Dec 2011]
CHSY1 Gene-Disease associations (from GenCC):
  • temtamy preaxial brachydactyly syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.1384562).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHSY1NM_014918.5 linkc.2320A>G p.Thr774Ala missense_variant Exon 3 of 3 ENST00000254190.4 NP_055733.2 Q86X52

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHSY1ENST00000254190.4 linkc.2320A>G p.Thr774Ala missense_variant Exon 3 of 3 1 NM_014918.5 ENSP00000254190.3 Q86X52
CHSY1ENST00000543813.2 linkn.*1635A>G non_coding_transcript_exon_variant Exon 3 of 3 2 ENSP00000496160.1 A0A2R8Y7B7
CHSY1ENST00000543813.2 linkn.*1635A>G 3_prime_UTR_variant Exon 3 of 3 2 ENSP00000496160.1 A0A2R8Y7B7

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152238
Hom.:
0
Cov.:
33
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
GnomAD2 exomes
AF:
0.00000399
AC:
1
AN:
250828
AF XY:
0.00
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461356
Hom.:
0
Cov.:
68
AF XY:
0.00000413
AC XY:
3
AN XY:
726940
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33450
American (AMR)
AF:
0.0000896
AC:
4
AN:
44638
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26122
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39692
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86140
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111766
Other (OTH)
AF:
0.00
AC:
0
AN:
60366
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.538
Heterozygous variant carriers
0
1
1
2
2
3
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:
152238
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74376
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41466
American (AMR)
AF:
0.0000655
AC:
1
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5204
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
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:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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

Temtamy preaxial brachydactyly syndrome Uncertain:1
Apr 05, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 774 of the CHSY1 protein (p.Thr774Ala). This variant is present in population databases (no rsID available, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with CHSY1-related conditions. ClinVar contains an entry for this variant (Variation ID: 966757). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt CHSY1 protein function with a negative predictive value of 80%. 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
Benign
0.073
BayesDel_addAF
Benign
-0.29
T
BayesDel_noAF
Benign
-0.58
CADD
Benign
17
DANN
Benign
0.95
DEOGEN2
Benign
0.014
T
Eigen
Benign
-0.26
Eigen_PC
Benign
-0.065
FATHMM_MKL
Uncertain
0.90
D
LIST_S2
Benign
0.78
T
M_CAP
Benign
0.0056
T
MetaRNN
Benign
0.14
T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
0.75
N
PhyloP100
2.7
PrimateAI
Uncertain
0.58
T
PROVEAN
Benign
-0.97
N
REVEL
Benign
0.033
Sift
Benign
0.31
T
Sift4G
Benign
0.58
T
Polyphen
0.0020
B
Vest4
0.15
MutPred
0.57
Gain of helix (P = 0.132);
MVP
0.29
MPC
0.32
ClinPred
0.24
T
GERP RS
4.8
Varity_R
0.14
gMVP
0.38
Mutation Taster
=53/47
polymorphism

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

Other links and lift over

dbSNP: rs556065115; hg19: chr15-101717682; API