18-49097401-C-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1_Moderate PM2 PP3_Strong PP5_Very_Strong

The NM_001353214.3(DYM):c.2025+1G>A variant causes a splice donor change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: DYM NM_001353214.3 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 6.71

Genes affected

DYM (HGNC:21317): (dymeclin) This gene encodes a protein which regulates Golgi-associated secretory pathways that are essential to endochondral bone formation during early development. This gene is also believed to play a role in early brain development. This gene is widely expressed in embryos and is particularly abundant in chodrocytes and brain tissues. It encodes a peripheral membrane protein which shuttles between the cytosol and Golgi complex. Mutations in this gene are associated with two types of recessive osteochondrodysplasia: Dyggve-Melchior-Clausen (DMC) dysplasia and Smith-McCort (SMC) dysplasia. [provided by RefSeq, Jun 2017]

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PVS1: Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.051954024 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 18-49097401-C-T is Pathogenic according to our data. Variant chr18-49097401-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 191091.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr18-49097401-C-T is described in Lovd as [Likely_pathogenic]. Variant chr18-49097401-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DYM	NM_001353214.3	c.2025+1G>A		splice_donor_variant		ENST00000675505.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DYM	ENST00000675505.1	c.2025+1G>A		splice_donor_variant			NM_001353214.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

research

Department Of Translational Genomics (developmental Genetics Section), King Faisal Specialist Hospital & Research Centre

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Dyggve-Melchior-Clausen syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

research

Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center

Mar 17, 2024

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.43
Cadd	Pathogenic	32
Dann	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Uncertain	0.97	D
MutationTaster	Benign	1.0	D;D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.99		Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs786205511; hg19: chr18-46623771;