chr2-74361525-G-C

Position:

• chr2-74361525-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_004082.5(DCTN1):​c.3811C>G​(p.Gln1271Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,856 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DCTN1 NM_004082.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.854

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 Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.113304526).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DCTN1	NM_004082.5	c.3811C>G	p.Gln1271Glu	missense_variant	32/32	ENST00000628224.3	NP_004073.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DCTN1	ENST00000628224.3	c.3811C>G	p.Gln1271Glu	missense_variant	32/32	5	NM_004082.5	ENSP00000487279	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461856 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727228

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

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: 0.00

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 30, 2020

Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). 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. This variant has not been reported in the literature in individuals with DCTN1-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces glutamine with glutamic acid at codon 1271 of the DCTN1 protein (p.Gln1271Glu). The glutamine residue is highly conserved and there is a small physicochemical difference between glutamine and glutamic acid. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.078
BayesDel_addAF	Benign	-0.11	T
BayesDel_noAF	Benign	-0.39
CADD	Benign	22
DANN	Benign	0.97
DEOGEN2	Benign	0.085	T;.;T;.;.;.;T;.
Eigen	Benign	-0.28
Eigen_PC	Benign	-0.050
FATHMM_MKL	Uncertain	0.85	D
LIST_S2	Uncertain	0.90	D;D;D;D;D;D;.;D
M_CAP	Benign	0.014	T
MetaRNN	Benign	0.11	T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.86	T
MutationAssessor	Benign	0.26	N;.;.;.;.;.;.;.
MutationTaster	Benign	0.89	N;N;N;N;N;N;N
PrimateAI	Benign	0.31	T
PROVEAN	Benign	-0.27	N;N;.;.;N;N;N;N
REVEL	Benign	0.15
Sift	Benign	0.21	T;T;.;.;T;T;T;T
Sift4G	Benign	0.43	T;T;T;T;T;T;T;T
Polyphen		0.0	B;.;.;B;.;.;.;.
Vest4		0.10
MutPred		0.20		Loss of MoRF binding (P = 0.0939);.;.;.;.;.;.;.;
MVP		0.64
MPC		0.12
ClinPred		0.18	T
GERP RS		5.6
Varity_R		0.094
gMVP		0.37

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

Other links and lift over

dbSNP: rs1673987624; hg19: chr2-74588652;