rs774026720

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PM1PM2PM5PP3_StrongPP5

The NM_153033.5(KCTD7):​c.335G>A​(p.Arg112His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,614,076 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R112C) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

KCTD7
NM_153033.5 missense

Scores

15
3
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:1

Conservation

PhyloP100: 9.24

Publications

6 publications found
Variant links:
Genes affected
KCTD7 (HGNC:21957): (potassium channel tetramerization domain containing 7) This gene encodes a member of the potassium channel tetramerization domain-containing protein family. Family members are identified on a structural basis and contain an amino-terminal domain similar to the T1 domain present in the voltage-gated potassium channel. Mutations in this gene have been associated with progressive myoclonic epilepsy-3. Alternative splicing results in multiple transcript variants.[provided by RefSeq, Jan 2011]
KCTD7 Gene-Disease associations (from GenCC):
  • progressive myoclonic epilepsy type 3
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Genomics England PanelApp, Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), Orphanet
  • progressive myoclonus epilepsy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 11 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_153033.5
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr7-66638272-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 1000932.We mark this variant Likely_pathogenic, oryginal submission is: [Conflicting_classifications_of_pathogenicity].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.976
PP5
Variant 7-66638273-G-A is Pathogenic according to our data. Variant chr7-66638273-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 206015.We mark this variant Likely_pathogenic, oryginal submission is: [Conflicting_classifications_of_pathogenicity].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCTD7NM_153033.5 linkc.335G>A p.Arg112His missense_variant Exon 3 of 4 ENST00000639828.2 NP_694578.1 Q96MP8-1A0A024RDN7
KCTD7NM_001167961.2 linkc.335G>A p.Arg112His missense_variant Exon 3 of 5 NP_001161433.1 Q96MP8-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCTD7ENST00000639828.2 linkc.335G>A p.Arg112His missense_variant Exon 3 of 4 2 NM_153033.5 ENSP00000492240.1 Q96MP8-1
ENSG00000284461ENST00000503687.2 linkn.165G>A non_coding_transcript_exon_variant Exon 2 of 13 2 ENSP00000421074.1 E9PHB8

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152184
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251378
AF XY:
0.00000736
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:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000410
AC:
6
AN:
1461892
Hom.:
0
Cov.:
32
AF XY:
0.00000413
AC XY:
3
AN XY:
727248
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:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1112010
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.00000657
AC:
1
AN:
152184
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74326
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41440
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68034
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
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000199
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Progressive myoclonic epilepsy type 3 Pathogenic:1Uncertain:1
Feb 21, 2020
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine with histidine at codon 112 of the KCTD7 protein (p.Arg112His). The arginine residue is highly conserved and there is a small physicochemical difference between arginine and histidine. This variant is present in population databases (rs774026720, ExAC 0.001%). This variant has been observed in individual(s) with clinical features of epilepsy and neurodevelopmental disorders (PMID: 29655203). ClinVar contains an entry for this variant (Variation ID: 206015). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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. -

Dec 30, 2017
Department Of Genetics, Sultan Qaboos University Hospital, Sultan Qaboos University
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:1
Dec 05, 2014
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The R112H variant that is likely pathogenic has been identified in the KCTD7 gene. The R112H variant has not been published as a mutation, nor has it been reported as a benign polymorphism to our knowledge. It was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. This substitution alters a highly conserved position predicted to be within the BTB domain of the KCTD7 protein. In silico analysis predicts this variant is probably damaging to the protein structure/function. However, the R112H variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties. Therefore, this variant is a strong candidate for a pathogenic mutation, however the possibility that it is a benign variant cannot be excluded. The variant is found in EPILEPSY panel(s). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.95
BayesDel_addAF
Pathogenic
0.35
D
BayesDel_noAF
Pathogenic
0.26
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.85
D;.;.;.;.;.
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.96
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.98
D;D;D;D;D;D
M_CAP
Uncertain
0.19
D
MetaRNN
Pathogenic
0.98
D;D;D;D;D;D
MetaSVM
Uncertain
0.16
D
MutationAssessor
Pathogenic
3.5
H;.;.;H;.;.
PhyloP100
9.2
PrimateAI
Uncertain
0.71
T
PROVEAN
Pathogenic
-4.9
.;D;.;D;.;.
REVEL
Pathogenic
0.82
Sift
Pathogenic
0.0
.;D;.;D;.;.
Sift4G
Pathogenic
0.0
.;D;.;D;.;.
Polyphen
1.0
D;.;.;.;.;.
Vest4
0.96
MutPred
0.89
Loss of methylation at R112 (P = 0.085);Loss of methylation at R112 (P = 0.085);Loss of methylation at R112 (P = 0.085);Loss of methylation at R112 (P = 0.085);Loss of methylation at R112 (P = 0.085);Loss of methylation at R112 (P = 0.085);
MVP
0.90
ClinPred
0.99
D
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.83
gMVP
0.88
Mutation Taster
=15/85
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
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: rs774026720; hg19: chr7-66103260; COSMIC: COSV99299062; COSMIC: COSV99299062; API