Genetic Variant NM_014918.5:c.2377A>G (chr15-101177420-T-C) – ACMG Classification: Likely_benign (-2 pts)

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_014918.5(CHSY1):c.2377A>G(p.Ser793Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,190 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: not found (cov: 33)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

CHSY1
NM_014918.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.30

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 links:

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ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.057504).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHSY1	NM_014918.5 link	c.2377A>G	p.Ser793Gly	missense_variant	Exon 3 of 3	ENST00000254190.4	NP_055733.2	Q86X52

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
CHSY1	ENST00000254190.4 link	c.2377A>G	p.Ser793Gly	missense_variant	Exon 3 of 3	1	NM_014918.5	ENSP00000254190.3	Q86X52
CHSY1	ENST00000543813.2 link	n.*1692A>G		non_coding_transcript_exon_variant	Exon 3 of 3	2		ENSP00000496160.1	A0A2R8Y7B7
CHSY1	ENST00000543813.2 link	n.*1692A>G		3_prime_UTR_variant	Exon 3 of 3	2		ENSP00000496160.1	A0A2R8Y7B7

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000400

AC:

AN:

249998

Hom.:

AF XY:

0.00000739

AC XY:

AN XY:

135240

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:

0.00000886

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000342

AC:

AN:

1461190

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

726820

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

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:

0.00000450

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000468

Hom.:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Temtamy preaxial brachydactyly syndrome

Uncertain:1

Oct 13, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine, which is neutral and polar, with glycine, which is neutral and non-polar, at codon 793 of the CHSY1 protein (p.Ser793Gly). This variant is not present in population databases (gnomAD no frequency). 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: 1506765). 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 glycine 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

Benign

0.054

BayesDel_addAF

Benign

-0.32

BayesDel_noAF

Benign

-0.70

CADD

Benign

DANN

Benign

0.75

DEOGEN2

Benign

0.0072

Eigen

Benign

-0.67

Eigen_PC

Benign

-0.51

FATHMM_MKL

Benign

0.75

LIST_S2

Benign

0.53

M_CAP

Benign

0.0045

MetaRNN

Benign

0.058

MetaSVM

Benign

-1.0

MutationAssessor

Benign

0.55

PrimateAI

Benign

0.33

PROVEAN

Benign

-0.080

REVEL

Benign

0.042

Sift

Benign

0.22

Sift4G

Benign

0.26

Polyphen

0.0

Vest4

0.056

MutPred

0.099

Loss of glycosylation at S793 (P = 0.0311);

MVP

0.28

MPC

0.29

ClinPred

0.077

GERP RS

1.8

Varity_R

0.059

gMVP

0.33

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