20-10405647-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2BP4

The NM_170784.3(MKKS):​c.1313G>A​(p.Cys438Tyr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,826 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C438G) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

MKKS
NM_170784.3 missense

Scores

3
4
12

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 0.533

Publications

1 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: Uncertain_significance. The variant received 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.3477963).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MKKSNM_170784.3 linkc.1313G>A p.Cys438Tyr missense_variant Exon 6 of 6 ENST00000347364.7 NP_740754.1 Q9NPJ1B7Z3W9
MKKSNM_018848.3 linkc.1313G>A p.Cys438Tyr missense_variant Exon 6 of 6 NP_061336.1 Q9NPJ1B7Z3W9
MKKSNR_072977.2 linkn.674G>A non_coding_transcript_exon_variant Exon 5 of 5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MKKSENST00000347364.7 linkc.1313G>A p.Cys438Tyr missense_variant Exon 6 of 6 1 NM_170784.3 ENSP00000246062.4 Q9NPJ1
MKKSENST00000399054.6 linkc.1313G>A p.Cys438Tyr missense_variant Exon 6 of 6 1 ENSP00000382008.2 Q9NPJ1
MKKSENST00000651692.1 linkc.1313G>A p.Cys438Tyr missense_variant Exon 7 of 7 ENSP00000498849.1 Q9NPJ1
MKKSENST00000652676.1 linkn.957G>A non_coding_transcript_exon_variant Exon 7 of 7

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461826
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
727220
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111970
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Feb 22, 2016
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Oct 31, 2019
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.070
BayesDel_addAF
Benign
-0.014
T
BayesDel_noAF
Benign
-0.26
CADD
Benign
17
DANN
Benign
0.76
DEOGEN2
Pathogenic
0.85
D;D
Eigen
Benign
-0.41
Eigen_PC
Benign
-0.53
FATHMM_MKL
Benign
0.21
N
LIST_S2
Benign
0.61
.;T
M_CAP
Uncertain
0.099
D
MetaRNN
Benign
0.35
T;T
MetaSVM
Uncertain
-0.032
T
MutationAssessor
Pathogenic
3.0
M;M
PhyloP100
0.53
PrimateAI
Benign
0.36
T
PROVEAN
Pathogenic
-5.2
D;D
REVEL
Uncertain
0.33
Sift
Benign
0.060
T;T
Sift4G
Uncertain
0.0060
D;D
Polyphen
0.69
P;P
Vest4
0.13
MutPred
0.58
Gain of phosphorylation at C438 (P = 0.0113);Gain of phosphorylation at C438 (P = 0.0113);
MVP
0.93
MPC
0.27
ClinPred
0.95
D
GERP RS
0.34
Varity_R
0.23
gMVP
0.80
Mutation Taster
=77/23
polymorphism

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: rs758821712; hg19: chr20-10386295; API