chr2-74363033-T-A

Position:

• chr2-74363033-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_004082.5(DCTN1):​c.3490A>T​(p.Thr1164Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,640 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DCTN1 NM_004082.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.23

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 Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.08167601).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DCTN1	NM_004082.5	c.3490A>T	p.Thr1164Ser	missense_variant	29/32	ENST00000628224.3	NP_004073.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DCTN1	ENST00000628224.3	c.3490A>T	p.Thr1164Ser	missense_variant	29/32	5	NM_004082.5	ENSP00000487279	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461640 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727094

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

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

Nov 22, 2020

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 tolerated, 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 conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces threonine with serine at codon 1164 of the DCTN1 protein (p.Thr1164Ser). The threonine residue is highly conserved and there is a small physicochemical difference between threonine and serine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.082
BayesDel_addAF	Benign	-0.079	T
BayesDel_noAF	Benign	-0.35
CADD	Benign	18
DANN	Benign	0.92
DEOGEN2	Benign	0.086	T;.;T;.;.;.;T;.
Eigen	Benign	-0.63
Eigen_PC	Benign	-0.47
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Benign	0.75	T;T;T;T;T;T;.;T
M_CAP	Benign	0.028	D
MetaRNN	Benign	0.082	T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.93	T
MutationAssessor	Benign	1.0	L;.;.;.;.;.;.;.
MutationTaster	Benign	0.55	N;N;N;N;N;N;N
PrimateAI	Benign	0.39	T
PROVEAN	Benign	-0.18	N;N;.;.;N;N;N;N
REVEL	Benign	0.050
Sift	Benign	0.033	D;D;.;.;D;D;D;D
Sift4G	Benign	0.20	T;T;T;D;D;T;T;T
Polyphen		0.075	B;.;.;B;.;.;.;.
Vest4		0.13
MutPred		0.18		Loss of catalytic residue at T1164 (P = 0.0419);.;.;.;.;.;.;.;
MVP		0.60
MPC		0.096
ClinPred		0.17	T
GERP RS		2.7
Varity_R		0.031
gMVP		0.22

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr2-74590160; COSMIC: COSV62619671; COSMIC: COSV62619671;