rs1470946965

Positions:

• chr2-74366607-A-G
• chr2-74366607-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_004082.5(DCTN1):​c.2480T>C​(p.Leu827Pro) 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. 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: 8.88

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.942

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DCTN1	NM_004082.5	c.2480T>C	p.Leu827Pro	missense_variant	22/32	ENST00000628224.3	NP_004073.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DCTN1	ENST00000628224.3	c.2480T>C	p.Leu827Pro	missense_variant	22/32	5	NM_004082.5	ENSP00000487279	A1

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 03, 2017

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. 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 and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with DCTN1-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces leucine with proline at codon 827 of the DCTN1 protein (p.Leu827Pro). The leucine residue is highly conserved and there is a moderate physicochemical difference between leucine and proline. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.44	D
BayesDel_noAF	Pathogenic	0.40
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.59	D;.;T;.;.;.;T;.
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.95	D;D;D;D;D;D;.;D
M_CAP	Pathogenic	0.36	D
MetaRNN	Pathogenic	0.94	D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.55	D
MutationAssessor	Uncertain	2.7	M;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-4.7	D;D;.;.;D;D;D;D
REVEL	Pathogenic	0.90
Sift	Uncertain	0.0010	D;D;.;.;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;D;D;D
Polyphen		1.0	D;.;.;D;.;.;.;.
Vest4		0.98
MutPred		0.77		Loss of stability (P = 0.0071);.;.;.;.;.;.;.;
MVP		0.99
MPC		0.68
ClinPred		1.0	D
GERP RS		5.3
Varity_R		0.85
gMVP		0.93

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs1470946965; hg19: chr2-74593734;