17-58206081-A-G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PM4

The NM_017777.4(MKS1):​c.1678T>C​(p.Ter560Glnext*?) variant causes a stop lost change. The variant allele was found at a frequency of 0.00000559 in 1,610,218 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

MKS1
NM_017777.4 stop_lost

Scores

1
1
5

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 3.96

Publications

2 publications found
Variant links:
Genes affected
MKS1 (HGNC:7121): (MKS transition zone complex subunit 1) The protein encoded by this gene localizes to the basal body and is required for formation of the primary cilium in ciliated epithelial cells. Mutations in this gene result in Meckel syndrome type 1 and in Bardet-Biedl syndrome type 13. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Sep 2009]
MKS1 Gene-Disease associations (from GenCC):
  • Meckel syndrome, type 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Myriad Women’s Health, Labcorp Genetics (formerly Invitae)
  • Bardet-Biedl syndrome 13
    Inheritance: Unknown, AR Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, G2P
  • Joubert syndrome 28
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • Bardet-Biedl syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Joubert syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Joubert syndrome with ocular defect
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Meckel syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM4
Stoplost variant in NM_017777.4 Downstream stopcodon found after 16 codons.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MKS1NM_017777.4 linkc.1678T>C p.Ter560Glnext*? stop_lost Exon 18 of 18 ENST00000393119.7 NP_060247.2 Q9NXB0-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MKS1ENST00000393119.7 linkc.1678T>C p.Ter560Glnext*? stop_lost Exon 18 of 18 1 NM_017777.4 ENSP00000376827.2 Q9NXB0-1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152140
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000412
AC:
6
AN:
1458078
Hom.:
0
Cov.:
32
AF XY:
0.00000414
AC XY:
3
AN XY:
725170
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33414
American (AMR)
AF:
0.00
AC:
0
AN:
44164
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26026
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39632
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85734
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52926
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5234
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1110780
Other (OTH)
AF:
0.00
AC:
0
AN:
60168
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.517
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152140
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74336
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41446
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68008
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Dec 19, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: MKS1 c.1678T>C (p.X560GlnextX51) changes the termination codon and is predicted to lead to an extended protein with additional amino acids added to the normal C-terminus. MKS1 c.1678T>C (p.X560GlnextX51) causes a frameshift which results in an extension of the protein. The variant was absent in 239006 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.1678T>C in individuals affected with Meckel Syndrome Type 1 and no experimental evidence demonstrating its impact on protein function have been reported. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation and classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

MKS1-related disorder Uncertain:1
May 30, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The MKS1 c.1678T>C variant is predicted to result in extension of the open reading frame (p.*560Glnext*51). To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.013% of alleles in individuals of European (Non-Finnish) descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Meckel-Gruber syndrome;C0431399:Joubert syndrome Uncertain:1
Sep 24, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change disrupts the translational stop signal of the MKS1 mRNA. It is expected to extend the length of the MKS1 protein by 51 additional amino acid residues. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with MKS1-related conditions. 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
BayesDel_addAF
Benign
-0.072
T
BayesDel_noAF
Benign
-0.34
CADD
Benign
14
DANN
Benign
0.81
Eigen
Pathogenic
0.79
Eigen_PC
Uncertain
0.57
FATHMM_MKL
Benign
0.50
N
PhyloP100
4.0
Vest4
0.078
GERP RS
3.9
Mutation Taster
=8/192
disease causing

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

Other links and lift over

dbSNP: rs1286667377; hg19: chr17-56283442; API