2-74371625-G-C

Variant names:

• chr2-74371625-G-C
• NM_004082.5:c.557C>G

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_004082.5(DCTN1):​c.557C>G​(p.Pro186Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000834 in 1,438,700 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000083 (0 hom.)
• Consequence: DCTN1 NM_004082.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.08

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_benign. Variant got -4 ACMG points.

• BS2: High AC in GnomAdExome4 at 12 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DCTN1	NM_004082.5	c.557C>G	p.Pro186Arg	missense_variant	Exon 8 of 32	ENST00000628224.3	NP_004073.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DCTN1	ENST00000628224.3	c.557C>G	p.Pro186Arg	missense_variant	Exon 8 of 32	5	NM_004082.5	ENSP00000487279.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000834 AC: 12 AN: 1438700 Hom.: 0 Cov.: 32 AF XY: 0.00000841 AC XY: 6 AN XY: 713362

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: 0.0000109

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

Dec 12, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 186 of the DCTN1 protein (p.Pro186Arg). 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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt DCTN1 protein function with a negative predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.41
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.070
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.57	D;.;T;.;.;.;T;.
Eigen	Uncertain	0.67
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D;D;D;D;D;D;.;D
M_CAP	Uncertain	0.16	D
MetaRNN	Uncertain	0.52	D;D;D;D;D;D;D;D
MetaSVM	Uncertain	-0.0024	T
MutationAssessor	Uncertain	2.4	M;.;.;.;.;.;.;.
PrimateAI	Pathogenic	0.84	D
PROVEAN	Uncertain	-4.0	D;D;.;.;D;D;D;D
REVEL	Uncertain	0.45
Sift	Uncertain	0.0090	D;D;.;.;T;D;D;D
Sift4G	Uncertain	0.0050	D;D;D;D;D;D;D;D
Polyphen		1.0	D;.;.;D;.;.;.;.
Vest4		0.61
MutPred		0.23		Loss of glycosylation at P186 (P = 0.0127);.;.;.;.;.;.;.;
MVP		0.98
MPC		1.5
ClinPred		0.97	D
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.8
Varity_R		0.21
gMVP		0.53

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: chr2-74598752;