15-101178374-G-A

Variant names:

• chr15-101178374-G-A
• rs1555492492
• NM_014918.5:c.1423C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_014918.5(CHSY1):​c.1423C>T​(p.Gln475*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: CHSY1 NM_014918.5 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.75
• Publications: 0 publications found

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

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.409 CDS is truncated, and there are 2 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 15-101178374-G-A is Pathogenic according to our data. Variant chr15-101178374-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 522064.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_014918.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHSY1	NM_014918.5	MANE Select	c.1423C>T	p.Gln475*	stop_gained	Exon 3 of 3	NP_055733.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHSY1	ENST00000254190.4	TSL:1 MANE Select	c.1423C>T	p.Gln475*	stop_gained	Exon 3 of 3	ENSP00000254190.3
	CHSY1	ENST00000543813.2	TSL:2	n.*738C>T		non_coding_transcript_exon	Exon 3 of 3	ENSP00000496160.1
	CHSY1	ENST00000543813.2	TSL:2	n.*738C>T		3_prime_UTR	Exon 3 of 3	ENSP00000496160.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 37

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Pathogenic:1

Sep 29, 2017

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.66
CADD	Pathogenic	44
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		9.8
Vest4		0.34
GERP RS		5.8
Mutation Taster		=8/192	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs1555492492; hg19: chr15-101718579;