2-74365509-C-A

Position:

chr2-74365509-C-A

Variant summary

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

The NM_004082.5(DCTN1):c.3029+6G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000415 in 1,614,018 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 2/2 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.00028 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000017 ( 0 hom. )

Consequence

DCTN1
NM_004082.5 splice_region, intron

Scores

Splicing: ADA: 0.0004955

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.216

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 links:

DCTN1 (HGNC:):

DCTN1 links:

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 (BayesDel_noAF=-0.36).

BS1

Variant frequency is greater than expected in population amr. gnomad4 allele frequency = 0.000276 (42/152132) while in subpopulation AMR AF= 0.00275 (42/15262). AF 95% confidence interval is 0.00209. There are 0 homozygotes in gnomad4. There are 30 alleles in male gnomad4 subpopulation. Median coverage is 32. 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 42 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DCTN1	NM_004082.5 linkuse as main transcript	c.3029+6G>T		splice_region_variant, intron_variant		ENST00000628224.3	NP_004073.2	Q14203-1Q6MZZ3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DCTN1	ENST00000628224.3 linkuse as main transcript	c.3029+6G>T		splice_region_variant, intron_variant		5	NM_004082.5	ENSP00000487279.2		Q14203-1E7EX90

Frequencies

GnomAD3 genomes

AF:

0.000276

AC:

AN:

152132

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00275

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000796

AC:

AN:

251364

Hom.:

AF XY:

0.0000736

AC XY:

AN XY:

135874

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000463

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000264

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000171

AC:

AN:

1461886

Hom.:

Cov.:

AF XY:

0.0000193

AC XY:

AN XY:

727242

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000425

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:

0.00000540

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.000276

AC:

AN:

152132

Hom.:

Cov.:

AF XY:

0.000404

AC XY:

AN XY:

74308

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00275

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000450

Hom.:

Bravo

AF:

0.000208

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

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

Oct 23, 2023

This sequence change falls in intron 25 of the DCTN1 gene. It does not directly change the encoded amino acid sequence of the DCTN1 protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs754143116, gnomAD 0.04%), and has an allele count higher than expected for a pathogenic variant. 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: 574930). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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

BayesDel_noAF

Benign

-0.36

CADD

Benign

DANN

Benign

0.75

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.0

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.00050

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over