DCTN1 p.Ala20Ala

Variant names:

• chr2-74378218-C-C
• NM_004082.5:c.

Your query was ambiguous. Multiple possible variants found:

• chr2-74378219--
• chr2-74378219-C-A
• chr2-74378219-C-G
• chr2-74378219-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_004082.5(DCTN1):​c. variant causes a exon region change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: DCTN1 NM_004082.5 exon_region
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -3.25
• Publications: 0 publications found

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: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• 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: Ambry Genetics, Orphanet, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• amyotrophic lateral sclerosis

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• distal hereditary motor neuropathy type 7

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004082.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DCTN1	NM_004082.5	MANE Select	c.		exon_region	Exon 2 of 32	NP_004073.2
	DCTN1	NM_001190837.2		c.		exon_region	Exon 2 of 31	NP_001177766.1	Q14203-6
	DCTN1	NM_001378991.1		c.		exon_region	Exon 2 of 32	NP_001365920.1	A0A7P0Z4C3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DCTN1	ENST00000628224.3	TSL:5 MANE Select	c.		exon_region	Exon 2 of 32	ENSP00000487279.2	Q14203-1
	DCTN1	ENST00000361874.8	TSL:1	c.		exon_region	Exon 2 of 31	ENSP00000354791.4	A0A804CDA6
	DCTN1	ENST00000409567.7	TSL:1	c.		exon_region	Exon 2 of 28	ENSP00000386843.3	Q14203-4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		-3.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr2-74605345;