rs755692930

Positions:

• chr4-3476404-C-A
• chr4-3476404-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP3_Moderate

The NM_173660.5(DOK7):​c.394C>A​(p.His132Asn) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 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. H132Q) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 31)
• Consequence: DOK7 NM_173660.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.87

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]

LOC105374355 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a domain IRS-type PTB (size 105) in uniprot entity DOK7_HUMAN there are 29 pathogenic changes around while only 0 benign (100%) in NM_173660.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.913

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DOK7	NM_173660.5	c.394C>A	p.His132Asn	missense_variant	4/7	ENST00000340083.6	NP_775931.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DOK7	ENST00000340083.6	c.394C>A	p.His132Asn	missense_variant	4/7	1	NM_173660.5	ENSP00000344432.5

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 39

GnomAD4 genome Cov.: 31

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

Labcorp Genetics (formerly Invitae), Labcorp

May 27, 2022

This sequence change replaces histidine, which is basic and polar, with asparagine, which is neutral and polar, at codon 132 of the DOK7 protein (p.His132Asn). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with DOK7-related conditions. ClinVar contains an entry for this variant (Variation ID: 566353). 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: "Probably 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	Pathogenic	0.91
BayesDel_addAF	Uncertain	0.088	D
BayesDel_noAF	Benign	-0.11
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.94	.;D
Eigen	Pathogenic	0.72
Eigen_PC	Uncertain	0.65
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.96	D;D
M_CAP	Uncertain	0.15	D
MetaRNN	Pathogenic	0.91	D;D
MetaSVM	Uncertain	0.29	D
MutationAssessor	Pathogenic	3.0	M;M
PrimateAI	Uncertain	0.69	T
PROVEAN	Pathogenic	-6.9	D;D
REVEL	Pathogenic	0.68
Sift	Uncertain	0.0030	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	.;D
Vest4		0.92
MutPred		0.69		Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);
MVP		0.93
MPC		0.019
ClinPred		0.99	D
GERP RS		4.4
Varity_R		0.90
gMVP		0.73

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: rs755692930; hg19: chr4-3478131;