rs1553465344

Variant names:

• chr2-74370989-T-A
• rs1553465344
• NM_004082.5:c.833A>T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_004082.5(DCTN1):​c.833A>T​(p.Glu278Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: DCTN1 NM_004082.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.03
• Publications: 0 publications found

Genes affected

DCTN1 (HGNC:2711): (dynactin subunit 1) This gene encodes the largest subunit of dynactin, a macromolecular complex consisting of 10 subunits ranging in size from 22 to 150 kD. Dynactin binds to both microtubules and cytoplasmic dynein. Dynactin is involved in a diverse array of cellular functions, including ER-to-Golgi transport, the centripetal movement of lysosomes and endosomes, spindle formation, chromosome movement, nuclear positioning, and axonogenesis. This subunit interacts with dynein intermediate chain by its domains directly binding to dynein and binds to microtubules via a highly conserved glycine-rich cytoskeleton-associated protein (CAP-Gly) domain in its N-terminus. Alternative splicing of this gene results in multiple transcript variants encoding distinct isoforms. Mutations in this gene cause distal hereditary motor neuronopathy type VIIB (HMN7B) which is also known as distal spinal and bulbar muscular atrophy (dSBMA). [provided by RefSeq, Oct 2008]

DCTN1 Gene-Disease associations (from GenCC):

• amyotrophic lateral sclerosis type 1

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• neuronopathy, distal hereditary motor, type 7B

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• Perry syndrome

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
• amyotrophic lateral sclerosis

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• distal hereditary motor neuropathy type 7

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DCTN1	NM_004082.5	c.833A>T	p.Glu278Val	missense_variant	Exon 9 of 32	ENST00000628224.3	NP_004073.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DCTN1	ENST00000628224.3	c.833A>T	p.Glu278Val	missense_variant	Exon 9 of 32	5	NM_004082.5	ENSP00000487279.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neuronopathy, distal hereditary motor, type 7B;C1862939:Amyotrophic lateral sclerosis type 1;C1868594:Perry syndrome Uncertain:1

Apr 03, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a DCTN1-related disease. This sequence change replaces glutamic acid with valine at codon 278 of the DCTN1 protein (p.Glu278Val). The glutamic acid residue is highly conserved and there is a moderate physicochemical difference between glutamic acid and valine. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies. In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.34
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Uncertain	0.11
CADD	Pathogenic	34
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.44	T;.;T;.;.;.;T;.
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	1.0	D;D;D;D;D;D;.;D
M_CAP	Pathogenic	0.43	D
MetaRNN	Uncertain	0.72	D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.51	D
MutationAssessor	Uncertain	2.3	M;.;.;.;.;.;.;.
PhyloP100		6.0
PrimateAI	Uncertain	0.58	T
PROVEAN	Pathogenic	-4.4	D;D;.;.;D;D;D;D
REVEL	Uncertain	0.63
Sift	Uncertain	0.0070	D;D;.;.;D;D;D;D
Sift4G	Uncertain	0.0040	D;D;D;D;D;D;D;D
Polyphen		1.0	D;.;.;D;.;.;.;.
Vest4		0.63
MutPred		0.19		Gain of methylation at K277 (P = 0.0557);.;.;.;.;.;.;.;
MVP		0.99
MPC		1.7
ClinPred		0.98	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.26
gMVP		0.47
Mutation Taster		=49/51	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.63		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.63		Position offset: 2

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

Other links and lift over

dbSNP: rs1553465344; hg19: chr2-74598116;