rs137853105

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1PM2PP3_ModeratePP5

The NM_017777.4(MKS1):​c.1476T>G​(p.Cys492Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000273 in 1,613,994 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. C492C) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

MKS1
NM_017777.4 missense

Scores

6
12
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:8U:3

Conservation

PhyloP100: 1.72

Publications

7 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: Likely_pathogenic. The variant received 7 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 11 uncertain in NM_017777.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.896
PP5
Variant 17-58206479-A-C is Pathogenic according to our data. Variant chr17-58206479-A-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1393.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MKS1NM_017777.4 linkc.1476T>G p.Cys492Trp missense_variant Exon 16 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.1476T>G p.Cys492Trp missense_variant Exon 16 of 18 1 NM_017777.4 ENSP00000376827.2 Q9NXB0-1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152134
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000561
AC:
14
AN:
249452
AF XY:
0.0000517
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000124
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000274
AC:
40
AN:
1461860
Hom.:
0
Cov.:
33
AF XY:
0.0000303
AC XY:
22
AN XY:
727242
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53390
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000360
AC:
40
AN:
1112008
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
3
6
9
12
15
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:
0.0000263
AC:
4
AN:
152134
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74298
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41442
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5174
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
67998
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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

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:
0.0000236
Hom.:
0
Bravo
AF:
0.0000189
ExAC
AF:
0.0000495
AC:
6
EpiCase
AF:
0.000273
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:8Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Bardet-Biedl syndrome 13 Pathogenic:2
Mar 30, 2024
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 01, 2008
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Bardet-Biedl syndrome 13;C3714506:Meckel syndrome, type 1;C4310705:Joubert syndrome 28 Pathogenic:1Uncertain:1
Mar 16, 2017
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Apr 04, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Meckel syndrome, type 1 Pathogenic:1
Feb 01, 2024
Laboratory of Medical Genetics, National & Kapodistrian University of Athens
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:curation

- -

Joubert syndrome 28 Pathogenic:1
Oct 01, 2021
Laboratory of Medical Genetics, National & Kapodistrian University of Athens
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PM2, PM3, PP3, PP5 -

Hypotonia;C0028738:Nystagmus;C0152427:Polydactyly Pathogenic:1
Jan 01, 2017
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Meckel-Gruber syndrome;C0431399:Joubert syndrome Pathogenic:1
Dec 15, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces cysteine, which is neutral and slightly polar, with tryptophan, which is neutral and slightly polar, at codon 492 of the MKS1 protein (p.Cys492Trp). This variant is present in population databases (rs137853105, gnomAD 0.01%). This missense change has been observed in individual(s) with Bardet-Biedl syndrome or Joubert syndrome (PMID: 18327255, 28497568, 34008892; internal data). 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: 1393). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt MKS1 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects MKS1 function (PMID: 18327255). For these reasons, this variant has been classified as Pathogenic. -

Bardet-Biedl syndrome Pathogenic:1
Jul 28, 2023
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

not provided Uncertain:1
Jan 20, 2021
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 18327255, 28497568) -

MKS1-related disorder Uncertain:1
Jun 07, 2023
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The MKS1 c.1476T>G variant is predicted to result in the amino acid substitution p.Cys492Trp. This variant has been reported in two individuals with BBS; these two individuals harbored a second variant of uncertain significance in MKS1 (Leitch et al. 2008. PubMed ID: 18327255; Summers et al. 2017. PubMed ID: 28497568). This variant is reported in 0.012% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/17-56283840-A-C). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.89
BayesDel_addAF
Uncertain
0.15
D
BayesDel_noAF
Pathogenic
0.23
CADD
Benign
23
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.80
D;.
Eigen
Uncertain
0.35
Eigen_PC
Uncertain
0.25
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Uncertain
0.92
D;D
M_CAP
Uncertain
0.16
D
MetaRNN
Pathogenic
0.90
D;D
MetaSVM
Uncertain
-0.27
T
MutationAssessor
Uncertain
2.8
M;.
PhyloP100
1.7
PrimateAI
Uncertain
0.78
T
PROVEAN
Pathogenic
-4.5
D;D
REVEL
Pathogenic
0.66
Sift
Uncertain
0.0010
D;D
Sift4G
Uncertain
0.0030
D;D
Polyphen
1.0
D;.
Vest4
0.97
MVP
0.90
MPC
1.1
ClinPred
0.92
D
GERP RS
0.48
Varity_R
0.96
gMVP
0.85
Mutation Taster
=2/98
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
Splicevardb
2.0
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: rs137853105; hg19: chr17-56283840; API