chr20-10412981-G-A

Variant summary

Our verdict is Benign. The variant received -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BA1

The NM_170784.3(MKKS):​c.534C>T​(p.Ile178Ile) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.126 in 1,613,754 control chromosomes in the GnomAD database, including 14,343 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.14 ( 1772 hom., cov: 32)
Exomes 𝑓: 0.12 ( 12571 hom. )

Consequence

MKKS
NM_170784.3 synonymous

Scores

2

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:11

Conservation

PhyloP100: 0.675

Publications

27 publications found
Variant links:
Genes affected
MKKS (HGNC:7108): (MKKS centrosomal shuttling protein) This gene encodes a protein which shares sequence similarity with other members of the type II chaperonin family. The encoded protein is a centrosome-shuttling protein and plays an important role in cytokinesis. This protein also interacts with other type II chaperonin members to form a complex known as the BBSome, which involves ciliary membrane biogenesis. This protein is encoded by a downstream open reading frame (dORF). Several upstream open reading frames (uORFs) have been identified, which repress the translation of the dORF, and two of which can encode small mitochondrial membrane proteins. Mutations in this gene have been observed in patients with Bardet-Biedl syndrome type 6, also known as McKusick-Kaufman syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2023]
MKKS Gene-Disease associations (from GenCC):
  • McKusick-Kaufman syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Orphanet
  • Bardet-Biedl syndrome 6
    Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • Bardet-Biedl syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -21 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.67).
BP6
Variant 20-10412981-G-A is Benign according to our data. Variant chr20-10412981-G-A is described in CliVar as Benign. Clinvar id is 21671.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr20-10412981-G-A is described in CliVar as Benign. Clinvar id is 21671.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr20-10412981-G-A is described in CliVar as Benign. Clinvar id is 21671.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr20-10412981-G-A is described in CliVar as Benign. Clinvar id is 21671.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr20-10412981-G-A is described in CliVar as Benign. Clinvar id is 21671.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=0.675 with no splicing effect.
BA1
GnomAd4 highest subpopulation (EAS) allele frequency at 95% confidence interval = 0.23 is higher than 0.05.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MKKSNM_170784.3 linkc.534C>T p.Ile178Ile synonymous_variant Exon 3 of 6 ENST00000347364.7 NP_740754.1 Q9NPJ1B7Z3W9
MKKSNM_018848.3 linkc.534C>T p.Ile178Ile synonymous_variant Exon 3 of 6 NP_061336.1 Q9NPJ1B7Z3W9
MKKSNR_072977.2 linkn.347-4178C>T intron_variant Intron 2 of 4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MKKSENST00000347364.7 linkc.534C>T p.Ile178Ile synonymous_variant Exon 3 of 6 1 NM_170784.3 ENSP00000246062.4 Q9NPJ1
MKKSENST00000399054.6 linkc.534C>T p.Ile178Ile synonymous_variant Exon 3 of 6 1 ENSP00000382008.2 Q9NPJ1
MKKSENST00000651692.1 linkc.534C>T p.Ile178Ile synonymous_variant Exon 4 of 7 ENSP00000498849.1 Q9NPJ1
MKKSENST00000652676.1 linkn.459-281C>T intron_variant Intron 3 of 6

Frequencies

GnomAD3 genomes
AF:
0.144
AC:
21885
AN:
151920
Hom.:
1767
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.192
Gnomad AMI
AF:
0.0263
Gnomad AMR
AF:
0.151
Gnomad ASJ
AF:
0.105
Gnomad EAS
AF:
0.241
Gnomad SAS
AF:
0.234
Gnomad FIN
AF:
0.118
Gnomad MID
AF:
0.0981
Gnomad NFE
AF:
0.107
Gnomad OTH
AF:
0.135
GnomAD2 exomes
AF:
0.140
AC:
35183
AN:
250930
AF XY:
0.143
show subpopulations
Gnomad AFR exome
AF:
0.191
Gnomad AMR exome
AF:
0.105
Gnomad ASJ exome
AF:
0.0999
Gnomad EAS exome
AF:
0.233
Gnomad FIN exome
AF:
0.115
Gnomad NFE exome
AF:
0.109
Gnomad OTH exome
AF:
0.135
GnomAD4 exome
AF:
0.124
AC:
181619
AN:
1461714
Hom.:
12571
Cov.:
34
AF XY:
0.127
AC XY:
92316
AN XY:
727156
show subpopulations
African (AFR)
AF:
0.195
AC:
6521
AN:
33478
American (AMR)
AF:
0.109
AC:
4865
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.101
AC:
2652
AN:
26134
East Asian (EAS)
AF:
0.245
AC:
9709
AN:
39694
South Asian (SAS)
AF:
0.240
AC:
20694
AN:
86248
European-Finnish (FIN)
AF:
0.116
AC:
6166
AN:
53316
Middle Eastern (MID)
AF:
0.135
AC:
778
AN:
5768
European-Non Finnish (NFE)
AF:
0.110
AC:
122151
AN:
1111962
Other (OTH)
AF:
0.134
AC:
8083
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
Heterozygous variant carriers
0
10093
20187
30280
40374
50467
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
4692
9384
14076
18768
23460
<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:
0.144
AC:
21912
AN:
152040
Hom.:
1772
Cov.:
32
AF XY:
0.150
AC XY:
11134
AN XY:
74322
show subpopulations
African (AFR)
AF:
0.193
AC:
7981
AN:
41458
American (AMR)
AF:
0.151
AC:
2307
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.105
AC:
364
AN:
3470
East Asian (EAS)
AF:
0.241
AC:
1248
AN:
5172
South Asian (SAS)
AF:
0.234
AC:
1125
AN:
4810
European-Finnish (FIN)
AF:
0.118
AC:
1249
AN:
10556
Middle Eastern (MID)
AF:
0.102
AC:
30
AN:
294
European-Non Finnish (NFE)
AF:
0.107
AC:
7302
AN:
67972
Other (OTH)
AF:
0.133
AC:
282
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
Heterozygous variant carriers
0
931
1862
2794
3725
4656
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
248
496
744
992
1240
<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:
0.129
Hom.:
858
Bravo
AF:
0.144
Asia WGS
AF:
0.213
AC:
741
AN:
3478
EpiCase
AF:
0.110
EpiControl
AF:
0.110

ClinVar

Significance: Benign
Submissions summary: Benign:11
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:4
-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Jul 07, 2016
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Apr 06, 2015
Eurofins Ntd Llc (ga)
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Benign:2
-
Breakthrough Genomics, Breakthrough Genomics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

-
Department of Ophthalmology and Visual Sciences Kyoto University
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:literature only

- -

MKKS-related disorder Benign:1
Apr 30, 2024
PreventionGenetics, part of Exact Sciences
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Bardet-Biedl syndrome;C0948368:McKusick-Kaufman syndrome Benign:1
Feb 03, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

McKusick-Kaufman syndrome Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Bardet-Biedl syndrome 6 Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Bardet-Biedl syndrome Benign:1
Oct 13, 2009
GeneReviews
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:curation

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.67
CADD
Benign
1.1
DANN
Benign
0.40
PhyloP100
0.68
Mutation Taster
=100/0
polymorphism (auto)

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: rs17852625; hg19: chr20-10393629; COSMIC: COSV61398029; COSMIC: COSV61398029; API