chr2-74370033-T-C

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 0P and 7B. BP4_ModerateBS1_SupportingBS2

The NM_004082.5(DCTN1):​c.1324A>G​(p.Met442Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000372 in 1,614,004 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000037 ( 0 hom. )

Consequence

DCTN1
NM_004082.5 missense

Scores

1
3
15

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 7.83
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -7 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.17937922).
BS1
Variant frequency is greater than expected in population nfe. gnomad4_exome allele frequency = 0.0000369 (54/1461892) while in subpopulation NFE AF= 0.000045 (50/1112012). AF 95% confidence interval is 0.0000346. There are 0 homozygotes in gnomad4_exome. There are 26 alleles in male gnomad4_exome subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High AC in GnomAd4 at 6 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
DCTN1NM_004082.5 linkc.1324A>G p.Met442Val missense_variant Exon 13 of 32 ENST00000628224.3 NP_004073.2 Q14203-1Q6MZZ3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
DCTN1ENST00000628224.3 linkc.1324A>G p.Met442Val missense_variant Exon 13 of 32 5 NM_004082.5 ENSP00000487279.2 Q14203-1E7EX90

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152112
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.000480
GnomAD3 exomes
AF:
0.0000119
AC:
3
AN:
251490
Hom.:
0
AF XY:
0.0000221
AC XY:
3
AN XY:
135920
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000369
AC:
54
AN:
1461892
Hom.:
0
Cov.:
33
AF XY:
0.0000358
AC XY:
26
AN XY:
727246
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000450
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152112
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74314
show subpopulations
Gnomad4 AFR
AF:
0.0000724
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.000480
Alfa
AF:
0.0000508
Hom.:
0
Bravo
AF:
0.0000227
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000259
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jul 06, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: DCTN1 c.1324A>G (p.Met442Val) results in a conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 1.2e-05 in 251490 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1324A>G has been reported in the literature in at least one individual affected with distal Hereditary Motor Neuronopathy (Antoniadi_2015). This report does not provide unequivocal conclusions about association of the variant with DCTN1-Related Disorders. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 26392352). One ClinVar submitter has assessed this variant since 2014, and classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

DCTN1-related disorder Uncertain:1
Sep 05, 2024
PreventionGenetics, part of Exact Sciences
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

The DCTN1 c.1324A>G variant is predicted to result in the amino acid substitution p.Met442Val. This variant has been reported as a variant of uncertain significance in an individual with hereditary motor neuropathy (Table S3, Antoniadi et al. 2015. PubMed ID: 26392352). This variant is reported in 0.0018% of alleles in individuals of European (Non-Finnish) descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Neuronopathy, distal hereditary motor, type 7B;C1862939:Amyotrophic lateral sclerosis type 1;C1868594:Perry syndrome Uncertain:1
May 04, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 442 of the DCTN1 protein (p.Met442Val). This variant is present in population databases (rs763480310, gnomAD 0.002%). This variant has not been reported in the literature in individuals affected with DCTN1-related conditions. ClinVar contains an entry for this variant (Variation ID: 468257). 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
Benign
0.14
BayesDel_addAF
Benign
-0.031
T
BayesDel_noAF
Benign
-0.27
CADD
Uncertain
24
DANN
Uncertain
0.98
DEOGEN2
Benign
0.12
T;.;T;.;.;.;T;.
Eigen
Benign
-0.085
Eigen_PC
Benign
0.17
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.97
D;D;D;D;D;D;.;D
M_CAP
Benign
0.016
T
MetaRNN
Benign
0.18
T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.85
T
MutationAssessor
Benign
0.34
N;.;.;.;.;.;.;.
PrimateAI
Uncertain
0.53
T
PROVEAN
Benign
-0.87
N;N;.;.;N;N;N;N
REVEL
Benign
0.17
Sift
Benign
0.32
T;T;.;.;T;T;T;T
Sift4G
Benign
0.21
T;T;T;T;T;T;T;T
Polyphen
0.0010
B;.;.;B;.;.;.;.
Vest4
0.24
MVP
0.72
MPC
0.60
ClinPred
0.14
T
GERP RS
5.7
Varity_R
0.10
gMVP
0.14

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs763480310; hg19: chr2-74597160; API