chr7-66638336-C-T

Variant names:

• chr7-66638336-C-T
• rs372103637
• NM_153033.5:c.398C>T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM1 PM2 BP4

The NM_153033.5(KCTD7):​c.398C>T​(p.Ala133Val) variant causes a missense change. The variant allele was found at a frequency of 0.0000279 in 1,614,120 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: 0.000029 (0 hom.)
• Consequence: KCTD7 NM_153033.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.52

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]

ENSG00000284461 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM1: In a domain BTB (size 98) in uniprot entity KCTD7_HUMAN there are 5 pathogenic changes around while only 1 benign (83%) in NM_153033.5
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.33911517).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCTD7	NM_153033.5	c.398C>T	p.Ala133Val	missense_variant	Exon 3 of 4	ENST00000639828.2	NP_694578.1
KCTD7	NM_001167961.2	c.398C>T	p.Ala133Val	missense_variant	Exon 3 of 5		NP_001161433.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCTD7	ENST00000639828.2	c.398C>T	p.Ala133Val	missense_variant	Exon 3 of 4	2	NM_153033.5	ENSP00000492240.1
ENSG00000284461	ENST00000503687.2	n.228C>T		non_coding_transcript_exon_variant	Exon 2 of 13	2		ENSP00000421074.1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152236 Hom.: 0 Cov.: 32

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: 0.0000287 AC: 42 AN: 1461884 Hom.: 0 Cov.: 32 AF XY: 0.0000303 AC XY: 22 AN XY: 727242

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000369

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152236 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74370

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000441

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000329 Hom.: 0

Bravo AF: 0.0000113

TwinsUK AF: 0.000270 AC: 1

ALSPAC AF: 0.00 AC: 0

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Progressive myoclonic epilepsy type 3 Uncertain:1

Aug 24, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces alanine with valine at codon 133 of the KCTD7 protein (p.Ala133Val). The alanine residue is moderately conserved and there is a small physicochemical difference between alanine and valine. This variant is present in population databases (rs372103637, ExAC 0.001%). This variant has not been reported in the literature in individuals affected with KCTD7-related conditions. 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 tolerated. 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
AlphaMissense	Uncertain	0.51
BayesDel_addAF	Benign	-0.081	T
BayesDel_noAF	Benign	-0.35
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.59	D;.;.;.;.;.
Eigen	Benign	0.15
Eigen_PC	Uncertain	0.32
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.95	D;D;D;D;D;D
M_CAP	Benign	0.0089	T
MetaRNN	Benign	0.34	T;T;T;T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.1	L;.;.;L;.;.
PrimateAI	Uncertain	0.67	T
PROVEAN	Benign	-2.0	.;N;.;N;.;.
REVEL	Benign	0.13
Sift	Benign	0.086	.;T;.;T;.;.
Sift4G	Uncertain	0.020	.;D;.;D;.;.
Polyphen		0.091	B;.;.;.;.;.
Vest4		0.49, 0.51
MVP		0.51
ClinPred		0.47	T
GERP RS		5.8
Varity_R		0.36
gMVP		0.72

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

LitVar

Other links and lift over

dbSNP: rs372103637; hg19: chr7-66103323;