2-74361506-A-G

Variant summary

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

The NM_004082.5(DCTN1):c.3830T>C(p.Ile1277Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign 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: 2.00

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=0.20175141).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DCTN1	NM_004082.5	c.3830T>C	p.Ile1277Thr	missense_variant	32/32	ENST00000628224.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DCTN1	ENST00000628224.3	c.3830T>C	p.Ile1277Thr	missense_variant	32/32	5	NM_004082.5	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

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

Invitae

Apr 21, 2022

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. This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 1277 of the DCTN1 protein (p.Ile1277Thr). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with DCTN1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C65"). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.37
BayesDel_addAF	Uncertain	0.079	D
BayesDel_noAF	Benign	-0.12
Cadd	Uncertain	24
Dann	Uncertain	0.99
DEOGEN2	Benign	0.11	T;.;T;.;.;.;T;.
Eigen	Benign	-0.052
Eigen_PC	Benign	0.14
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.92	D;D;D;D;D;D;.;D
M_CAP	Benign	0.064	D
MetaRNN	Benign	0.20	T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.32	T
MutationAssessor	Benign	1.1	L;.;.;.;.;.;.;.
MutationTaster	Benign	0.95	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.74	T
PROVEAN	Benign	-0.62	N;N;.;.;N;N;N;N
REVEL	Uncertain	0.33
Sift	Uncertain	0.0030	D;D;.;.;D;D;D;D
Sift4G	Uncertain	0.039	D;D;D;D;D;D;D;D
Polyphen		0.067	B;.;.;P;.;.;.;.
Vest4		0.49
MutPred		0.19		Loss of stability (P = 0.0012);.;.;.;.;.;.;.;
MVP		0.80
MPC		0.16
ClinPred		0.51	D
GERP RS		5.6
Varity_R		0.097
gMVP		0.49

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: chr2-74588633;