rs371723224

Variant summary

Our verdict is Benign. The variant received -10 ACMG points: 0P and 10B. BP4BP6BS1BS2

The NM_004082.5(DCTN1):​c.673C>T​(p.Arg225Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000496 in 1,613,724 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R225Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000051 ( 0 hom. )

Consequence

DCTN1
NM_004082.5 missense

Scores

3
10
6

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:5

Conservation

PhyloP100: 2.65

Publications

1 publications found
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]
DCTN1 Gene-Disease associations (from GenCC):
  • amyotrophic lateral sclerosis type 1
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • neuronopathy, distal hereditary motor, type 7B
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • Perry syndrome
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • amyotrophic lateral sclerosis
    Inheritance: AD Classification: MODERATE Submitted by: ClinGen
  • distal hereditary motor neuropathy type 7
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -10 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.40065676).
BP6
Variant 2-74371149-G-A is Benign according to our data. Variant chr2-74371149-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 453052.
BS1
Variant frequency is greater than expected in population nfe. GnomAdExome4 allele frequency = 0.0000506 (74/1461638) while in subpopulation NFE AF = 0.0000477 (53/1112010). AF 95% confidence interval is 0.0000372. There are 0 homozygotes in GnomAdExome4. There are 49 alleles in the male GnomAdExome4 subpopulation. Median coverage is 33. This position passed quality control check.
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.673C>T p.Arg225Trp missense_variant Exon 9 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.673C>T p.Arg225Trp missense_variant Exon 9 of 32 5 NM_004082.5 ENSP00000487279.2 Q14203-1E7EX90

Frequencies

GnomAD3 genomes
AF:
0.0000395
AC:
6
AN:
152086
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000438
AC:
11
AN:
251290
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.000198
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000791
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000506
AC:
74
AN:
1461638
Hom.:
0
Cov.:
33
AF XY:
0.0000674
AC XY:
49
AN XY:
727136
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.000536
AC:
14
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53178
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000477
AC:
53
AN:
1112010
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.484
Heterozygous variant carriers
0
5
10
14
19
24
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000395
AC:
6
AN:
152086
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74292
show subpopulations
African (AFR)
AF:
0.0000242
AC:
1
AN:
41404
American (AMR)
AF:
0.00
AC:
0
AN:
15258
Ashkenazi Jewish (ASJ)
AF:
0.000288
AC:
1
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000683
Hom.:
0
Bravo
AF:
0.0000302
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000576
AC:
7
EpiCase
AF:
0.000109
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:5
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Nov 21, 2017
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Arg225Trp variant (rs371723224) has not been reported in the medical literature, nor is it listed in gene-specific variant databases. The p.Arg225Trp variant is listed in the Genome Aggregation Database (gnomAD) browser with an overall allele frequency of 0.004% (identified in 10 out of 246,064 chromosomes). The arginine at codon 225 is highly conserved considering 10 species up to opossum (Alamut software v2.10.0), but computational analyses predict conflicting effects of this variant on protein structure/function (SIFT: damaging, PolyPhen2: benign). Therefore, based on the available information, the clinical significance of the p.Arg225Trp variant cannot be determined with certainty. -

Oct 23, 2017
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The R225W variant in the DCTN1 gene has not been reported previously as a pathogenic variant, nor as a benign variant, to our knowledge. The variant is observed in 2/9848 (0.02%) alleles from individuals of Ashkenazi Jewish background in large population cohorts (Lek et al., 2016). The variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position where amino acids with similar properties to Arginine are tolerated across species. In silico analysis predicts this variant is probably damaging to the protein structure/function. We interpret R225W as a variant of uncertain significance. -

DCTN1-related disorder Uncertain:1
Nov 09, 2023
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The DCTN1 c.673C>T variant is predicted to result in the amino acid substitution p.Arg225Trp. This variant was reported in an individual with a behavioral variant of frontotemporal dementia (Bartoletti-Stella et al 2018. PubMed ID: 29525180, Table 3). This variant is reported in 0.020% of alleles in individuals of Ashkenazi Jewish descent in gnomAD (http://gnomad.broadinstitute.org/variant/2-74598276-G-A). 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
Sep 26, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 225 of the DCTN1 protein (p.Arg225Trp). This variant is present in population databases (rs371723224, gnomAD 0.02%). This missense change has been observed in individual(s) with dementia (PMID: 29525180). ClinVar contains an entry for this variant (Variation ID: 453052). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on DCTN1 protein function. 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. -

not specified Benign:1
Dec 24, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: DCTN1 c.673C>T (p.Arg225Trp) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4.4e-05 in 251290 control chromosomes. The observed variant frequency is approximately 44 fold of the estimated maximal expected allele frequency for a pathogenic variant in DCTN1 causing Neuronopathy, distal hereditary motor, type 7B phenotype (1e-06). To our knowledge, no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 453052). Based on the evidence outlined above, the variant was classified as likely benign. -

Inborn genetic diseases Benign:1
Nov 02, 2021
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Neuronopathy, distal hereditary motor, type 7B Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Parkinsonian disorder Benign:1
Jan 17, 2020
Genetics and Molecular Pathology, SA Pathology
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The DCTN1 c.673C>T variant is classified as Likely Benign (BS4, PM2, PP3) This variant does not segregate with disease in this family (BS4). -

Perry syndrome Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.32
BayesDel_addAF
Benign
-0.048
T
BayesDel_noAF
Benign
-0.12
CADD
Pathogenic
26
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.48
T;.;T;.;.;.;T;.
Eigen
Uncertain
0.50
Eigen_PC
Uncertain
0.50
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Pathogenic
1.0
D;D;D;D;D;D;.;D
M_CAP
Uncertain
0.12
D
MetaRNN
Benign
0.40
T;T;T;T;T;T;T;T
MetaSVM
Uncertain
0.097
D
MutationAssessor
Benign
1.2
L;.;.;.;.;.;.;.
PhyloP100
2.7
PrimateAI
Uncertain
0.76
T
PROVEAN
Pathogenic
-4.6
D;D;.;.;D;D;D;D
REVEL
Uncertain
0.46
Sift
Uncertain
0.0010
D;D;.;.;D;D;D;D
Sift4G
Uncertain
0.0050
D;D;D;D;D;D;D;D
Polyphen
0.99
D;.;.;D;.;.;.;.
Vest4
0.44
MVP
0.93
MPC
1.5
ClinPred
0.79
D
GERP RS
4.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.31
gMVP
0.49
Mutation Taster
=3/97
disease causing

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

Other links and lift over

dbSNP: rs371723224; hg19: chr2-74598276; API