rs771414481

Variant names:

• chr18-49258463-G-A
• rs771414481
• NM_001353214.3:c.1282C>T

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001353214.3(DYM):​c.1282C>T​(p.Arg428*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000343 in 1,459,838 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: DYM NM_001353214.3 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 5.36
• Publications: 2 publications found

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]

DYM Gene-Disease associations (from GenCC):

• Dyggve-Melchior-Clausen disease

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics, Orphanet
• Smith-McCort dysplasia 1

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• Smith-McCort dysplasia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 18-49258463-G-A is Pathogenic according to our data. Variant chr18-49258463-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 191092.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DYM	NM_001353214.3	c.1282C>T	p.Arg428*	stop_gained	Exon 12 of 18	ENST00000675505.1	NP_001340143.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DYM	ENST00000675505.1	c.1282C>T	p.Arg428*	stop_gained	Exon 12 of 18		NM_001353214.3	ENSP00000501694.1
DYM	ENST00000269445.10	c.1282C>T	p.Arg428*	stop_gained	Exon 12 of 17	1		ENSP00000269445.6
DYM	ENST00000442713.6	c.712C>T	p.Arg238*	stop_gained	Exon 7 of 12	2		ENSP00000395942.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD2 exomes AF: 0.00000797 AC: 2 AN: 251090 AF XY: 0.00000737

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

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: 0.000163

GnomAD4 exome AF: 0.00000343 AC: 5 AN: 1459838 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 726390

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33460

American (AMR) AF: 0.0000224 AC: 1 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26114

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39664

South Asian (SAS) AF: 0.00 AC: 0 AN: 86210

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53322

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1110240

Other (OTH) AF: 0.00 AC: 0 AN: 60340

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.003572), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 31

Alfa AF: 0.00000994 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

-

Genomic Medicine Center of Excellence, King Faisal Specialist Hospital and Research Centre

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: research

- -

Jan 06, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Arg428*) in the DYM gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in DYM are known to be pathogenic (PMID: 12491225, 12554689, 18996921). This variant is present in population databases (rs771414481, gnomAD 0.003%). This premature translational stop signal has been observed in individual(s) with Dyggve-Melchior-Clausen disease (PMID: 29620724). ClinVar contains an entry for this variant (Variation ID: 191092). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	42
DANN	Uncertain	1.0
Eigen	Pathogenic	0.77
Eigen_PC	Uncertain	0.64
FATHMM_MKL	Uncertain	0.91	D
PhyloP100		5.4
Vest4		0.99
GERP RS		4.7
Mutation Taster		=0/200	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: rs771414481; hg19: chr18-46784833;