4-3493242-GC-GCC

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_StrongPM2PP5_Very_Strong

The NM_173660.5(DOK7):​c.1263dupC​(p.Ser422LeufsTer97) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000123 in 1,611,824 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.00012 ( 0 hom., cov: 34)
Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

DOK7
NM_173660.5 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:14

Conservation

PhyloP100: 0.0800
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 9 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 4-3493242-G-GC is Pathogenic according to our data. Variant chr4-3493242-G-GC is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1274.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
DOK7NM_173660.5 linkc.1263dupC p.Ser422LeufsTer97 frameshift_variant Exon 7 of 7 ENST00000340083.6 NP_775931.3 Q18PE1-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
DOK7ENST00000340083.6 linkc.1263dupC p.Ser422LeufsTer97 frameshift_variant Exon 7 of 7 1 NM_173660.5 ENSP00000344432.5 Q18PE1-1
DOK7ENST00000643608.1 linkc.831dupC p.Ser278LeufsTer258 frameshift_variant Exon 5 of 8 ENSP00000495701.1 A0A2R8Y701
DOK7ENST00000515886.5 linkc.333dupC p.Ser112LeufsTer97 frameshift_variant Exon 4 of 4 2 ENSP00000492194.1 A0A1W2PRA3
DOK7ENST00000507039.5 linkc.*484dupC 3_prime_UTR_variant Exon 7 of 7 2 ENSP00000423614.1 Q18PE1-4

Frequencies

GnomAD3 genomes
AF:
0.000125
AC:
19
AN:
152192
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.000289
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.000103
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000758
AC:
18
AN:
237478
Hom.:
0
AF XY:
0.0000920
AC XY:
12
AN XY:
130418
show subpopulations
Gnomad AFR exome
AF:
0.000206
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000990
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000115
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000123
AC:
179
AN:
1459632
Hom.:
0
Cov.:
95
AF XY:
0.000116
AC XY:
84
AN XY:
726084
show subpopulations
Gnomad4 AFR exome
AF:
0.000269
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000464
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.000143
Gnomad4 OTH exome
AF:
0.000116
GnomAD4 genome
AF:
0.000125
AC:
19
AN:
152192
Hom.:
0
Cov.:
34
AF XY:
0.000161
AC XY:
12
AN XY:
74354
show subpopulations
Gnomad4 AFR
AF:
0.000289
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.000103
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.000132
EpiCase
AF:
0.000109
EpiControl
AF:
0.000178

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:14
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Fetal akinesia deformation sequence 3 Pathogenic:3
Jun 01, 2022
Solve-RD Consortium
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: provider interpretation

Variant confirmed as disease-causing by referring clinical team -

Sep 29, 2006
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Mar 27, 2024
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Pathogenic:3
Jan 11, 2024
Revvity Omics, Revvity
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 07, 2024
GeneDx
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Identified with a second DOK7 variant without confirmation of phase in patients with congenital myasthenic syndromes (PMID: 16917026, 37273706, 22661499, 18626973); Frameshift variant predicted to result in protein truncation, as the last 83 amino acids are replaced with 96 different amino acids, and other loss-of-function variants have been reported downstream in HGMD; This variant is associated with the following publications: (PMID: 31589614, 21850686, 18161030, 32153140, 31880392, 33726816, 16917026, 37273706, 22661499, 18626973) -

Mar 13, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

PM2_moderate, PM3_very_strong, PS4 -

Congenital myasthenic syndrome 10 Pathogenic:2
Jun 11, 2019
Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Sep 29, 2006
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Rett syndrome Pathogenic:1
-
Kasturba Medical College, Manipal, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: research

- -

Congenital myasthenic syndrome 10;C4760599:Fetal akinesia deformation sequence 3 Pathogenic:1
May 31, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Fetal akinesia deformation sequence 1;C1850792:Congenital myasthenic syndrome 10 Pathogenic:1
Jan 12, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change results in a frameshift in the DOK7 gene (p.Ser422Leufs*97). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 83 amino acid(s) of the DOK7 protein and extend the protein by 13 additional amino acid residues. This variant is present in population databases (rs751257124, gnomAD 0.02%). This frameshift has been observed in individual(s) with congenital myasthenic syndrome and fetal akinesia deformation sequence (PMID: 16917026, 21850686, 22661499). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 1274). For these reasons, this variant has been classified as Pathogenic. -

Fetal akinesia deformation sequence 1 Pathogenic:1
May 28, 2019
Mendelics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Congenital myasthenic syndrome Pathogenic:1
Feb 28, 2020
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: DOK7 c.1263dupC (p.Ser422LeufsX97) causes a frameshift which results in an extension of the protein. The variant allele was found at a frequency of 7.6e-05 in 237478 control chromosomes (gnomAD). This frequency is not higher than expected for a pathogenic variant in DOK7 causing Congenital myasthenic syndrome (7.6e-05 vs 0.0014), allowing no conclusion about variant significance. c.1263dupC has been reported in the literature in compound heterozygous and homozygous individuals affected with Congenital myasthenic syndrome (Selcen_2008, Anderson_2008). These data indicate that the variant is very likely to be associated with disease. Two ClinVar submitters (evaluation after 2014) cite the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

DOK7-related disorder Pathogenic:1
Dec 11, 2023
PreventionGenetics, part of Exact Sciences
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

The DOK7 c.1263dupC variant is predicted to result in a frameshift and premature protein termination (p.Ser422Leufs*97). This variant has been reported in individuals with autosomal recessive congenital myasthenic syndrome (Beeson et al. 2006. PubMed ID: 16917026; Anderson et al. 2008. PubMed ID: 18161030; Cossins et al. 2012. PubMed ID: 22661499). It has also been reported in the homozygous state in a case of fetal akinesia deformation sequence (Table 1, Bruno et al. 2011. PubMed ID: 21850686). This variant is reported in 0.017% of alleles in individuals of African descent in gnomAD. Frameshift variants in DOK7 are expected to be pathogenic. This variant is interpreted as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs606231129; hg19: chr4-3494969; API