4-3485644-G-T

Variant summary

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

The NM_173660.5(DOK7):c.638G>T(p.Arg213Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000138 in 1,448,216 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R213Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: DOK7 NM_173660.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.44

Genes affected

DOK7 (HGNC:26594): (docking protein 7) The protein encoded by this gene is essential for neuromuscular synaptogenesis. The protein functions in aneural activation of muscle-specific receptor kinase, which is required for postsynaptic differentiation, and in the subsequent clustering of the acetylcholine receptor in myotubes. This protein can also induce autophosphorylation of muscle-specific receptor kinase. Mutations in this gene are a cause of familial limb-girdle myasthenia autosomal recessive, which is also known as congenital myasthenic syndrome type 1B. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DOK7	NM_173660.5	c.638G>T	p.Arg213Leu	missense_variant	5/7	ENST00000340083.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DOK7	ENST00000340083.6	c.638G>T	p.Arg213Leu	missense_variant	5/7	1	NM_173660.5	P1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 0.00000138 AC: 2 AN: 1448216 Hom.: 0 Cov.: 33 AF XY: 0.00000139 AC XY: 1 AN XY: 719994

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.0000192

Gnomad4 NFE exome AF: 9.05e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 34

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Fetal akinesia deformation sequence 1;C1850792:Congenital myasthenic syndrome 10 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Apr 02, 2018

This sequence change replaces arginine with leucine at codon 213 of the DOK7 protein (p.Arg213Leu). The arginine residue is highly conserved and there is a moderate physicochemical difference between arginine and leucine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with DOK7-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.23
BayesDel_addAF	Uncertain	0.16	D
BayesDel_noAF	Uncertain	-0.010
Cadd	Uncertain	26
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.61	D;.
Eigen	Uncertain	0.30
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Uncertain	0.94	D;D
M_CAP	Pathogenic	0.41	D
MetaRNN	Uncertain	0.61	D;D
MetaSVM	Uncertain	0.23	D
MutationTaster	Benign	0.99	D;D;D
PrimateAI	Uncertain	0.73	T
PROVEAN	Pathogenic	-5.2	D;.
REVEL	Uncertain	0.60
Sift	Uncertain	0.0030	D;.
Sift4G	Uncertain	0.0050	D;.
Polyphen		0.33	B;.
Vest4		0.78
MutPred		0.41		Loss of glycosylation at P217 (P = 0.02);.;
MVP		0.86
MPC		0.0095
ClinPred		0.99	D
GERP RS		2.8
Varity_R		0.67
gMVP		0.60

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: rs371408752; hg19: chr4-3487371;