NM_001927.4:c.1226T>C

Variant names:

• chr2-219421542-T-C
• rs397516687
• NM_001927.4:c.1226T>C

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_001927.4(DES):​c.1226T>C​(p.Leu409Pro) variant causes a missense 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. 14/23 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. L409L) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 31)
• Consequence: DES NM_001927.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.91
• Publications: 0 publications found

Genes affected

DES (HGNC:2770): (desmin) This gene encodes a muscle-specific class III intermediate filament. Homopolymers of this protein form a stable intracytoplasmic filamentous network connecting myofibrils to each other and to the plasma membrane. Mutations in this gene are associated with desmin-related myopathy, a familial cardiac and skeletal myopathy (CSM), and with distal myopathies. [provided by RefSeq, Jul 2008]

DES Gene-Disease associations (from GenCC):

• dilated cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• dilated cardiomyopathy 1I

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• myofibrillar myopathy 1

  Inheritance: AD, AR, SD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• atrioventricular block

  Inheritance: AD, AR Classification: STRONG Submitted by: Genomics England PanelApp
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• neurogenic scapuloperoneal syndrome, Kaeser type

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 18 uncertain in NM_001927.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 32 curated pathogenic missense variants (we use a threshold of 10). The gene has 2 curated benign missense variants. Gene score misZ: 1.7729 (below the threshold of 3.09). Trascript score misZ: 0.36303 (below the threshold of 3.09). GenCC associations: The gene is linked to myofibrillar myopathy 1, dilated cardiomyopathy 1I, atrioventricular block, arrhythmogenic right ventricular cardiomyopathy, dilated cardiomyopathy, familial isolated dilated cardiomyopathy, neurogenic scapuloperoneal syndrome, Kaeser type.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001927.4. 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
	DES	NM_001927.4	MANE Select	c.1226T>C	p.Leu409Pro	missense	Exon 6 of 9	NP_001918.3
	DES	NM_001382708.1		c.1223T>C	p.Leu408Pro	missense	Exon 6 of 9	NP_001369637.1
	DES	NM_001382712.1		c.1226T>C	p.Leu409Pro	missense	Exon 6 of 9	NP_001369641.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DES	ENST00000373960.4	TSL:1 MANE Select	c.1226T>C	p.Leu409Pro	missense	Exon 6 of 9	ENSP00000363071.3
	DES	ENST00000477226.6	TSL:4	n.700T>C		non_coding_transcript_exon	Exon 5 of 8
	DES	ENST00000492726.1	TSL:4	n.621T>C		non_coding_transcript_exon	Exon 5 of 6

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Jan 07, 2011

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant classified as Uncertain Significance - Favor Pathogenic. The Leu409Pro v ariant has not been reported in the literature and has not been previously detec ted in over 254 Caucasian probands tested by our laboratory. Leucine (Leu) at p osition 409 is conserved across mammals and frogs, increasing the likelihood tha t the change is pathogenic. In addition, computational analyses (PolyPhen2, SIFT , AlignGVGD) suggest that the Leu409Pro variant may impact the protein. However, this information is not predictive enough to assume pathogenicity. In summary, evolutionary conservation and computational predictions support a pathogenic rol e but additional studies are necessary to determine the clinical significance of the Leu409Pro variant with certainty. Please note: Desmin variants are assoc iated with a variable clinical phenotype referred to as desmin-related myopathy (OMIM #601419) or myofibrillar myopathy, which can manifest as isolated myopathy (proximal or distal) or isolated cardiomyopathies (including DCM and RCM). Sen sory symptoms (muscle stiffness, aching, and cramps) are present in a small port ion of individuals. Peripheral neuropathy is present in about 20% and cardiomyop athy in 15%-30% of affected individuals.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
CardioboostCm	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	34
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.96	D
Eigen	Pathogenic	0.99
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.78	T
M_CAP	Pathogenic	0.59	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.9	H
PhyloP100		7.9
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-6.0	D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.99
MutPred		0.92		Loss of stability (P = 0.0369)
MVP		0.99
MPC		1.9
ClinPred		1.0	D
GERP RS		4.9
Varity_R		0.98
gMVP		0.99
Mutation Taster		=2/98	disease causing

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: rs397516687; hg19: chr2-220286264;