9-105615299-G-T

Variant names:

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_001079802.2(FKTN):c.802G>T(p.Val268Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,613,910 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

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

Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

FKTN
NM_001079802.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 0.777

Publications

0 publications found

Variant links:

Genes affected

FKTN (HGNC:3622): (fukutin) The protein encoded by this gene is a putative transmembrane protein that is localized to the cis-Golgi compartment, where it may be involved in the glycosylation of alpha-dystroglycan in skeletal muscle. The encoded protein is thought to be a glycosyltransferase and could play a role in brain development. Defects in this gene are a cause of Fukuyama-type congenital muscular dystrophy (FCMD), Walker-Warburg syndrome (WWS), limb-girdle muscular dystrophy type 2M (LGMD2M), and dilated cardiomyopathy type 1X (CMD1X). Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Nov 2010]

FKTN Gene-Disease associations (from GenCC):

autosomal recessive limb-girdle muscular dystrophy type 2M
Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P
muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 4
Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet, G2P
myopathy caused by variation in FKTN
Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
familial isolated dilated cardiomyopathy
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
congenital muscular dystrophy without intellectual disability
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
muscle-eye-brain disease
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
muscular dystrophy-dystroglycanopathy, type A
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
dilated cardiomyopathy 1X
Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

FKTN links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.070474565).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001079802.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
FKTN	NM_001079802.2	MANE Select	c.802G>T	p.Val268Leu	missense	Exon 8 of 11	NP_001073270.1
FKTN	NM_001351496.2		c.802G>T	p.Val268Leu	missense	Exon 9 of 12	NP_001338425.1
FKTN	NM_006731.2		c.802G>T	p.Val268Leu	missense	Exon 7 of 10	NP_006722.2

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
FKTN	ENST00000357998.10	TSL:5 MANE Select	c.802G>T	p.Val268Leu	missense	Exon 8 of 11	ENSP00000350687.6
FKTN	ENST00000223528.6	TSL:1	c.802G>T	p.Val268Leu	missense	Exon 7 of 10	ENSP00000223528.2
FKTN	ENST00000602526.1	TSL:1	n.*840G>T		non_coding_transcript_exon	Exon 8 of 11	ENSP00000473347.1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152242

Hom.:

Cov.:

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:

AN:

251454

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:

0.0000544

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000274

AC:

AN:

1461668

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727154

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33480

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26134

East Asian (EAS)

AF:

0.00

AC:

AN:

39694

South Asian (SAS)

AF:

0.00

AC:

AN:

86254

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53400

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

8.99e-7

AC:

AN:

1111822

Other (OTH)

AF:

0.0000497

AC:

AN:

60392

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.413

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

AN:

152242

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74378

show subpopulations

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.00

AC:

AN:

41464

American (AMR)

AF:

0.00

AC:

AN:

15284

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5202

South Asian (SAS)

AF:

0.00

AC:

AN:

4834

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10624

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

68040

Other (OTH)

AF:

0.00

AC:

AN:

2094

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.325

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Feb 17, 2016

Stanford Center for Inherited Cardiovascular Disease, Stanford University

Significance:Uncertain significance

Review Status:no assertion criteria provided

Collection Method:provider interpretation

Jun 06, 2022

GeneDx

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge

Walker-Warburg congenital muscular dystrophy

Uncertain:2

Aug 26, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 268 of the FKTN protein (p.Val268Leu). This variant is present in population databases (no rsID available, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with FKTN-related conditions. ClinVar contains an entry for this variant (Variation ID: 238268). 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.

Nov 16, 2020

Natera, Inc.

Significance:Uncertain significance

Review Status:no assertion criteria provided

Collection Method:clinical testing

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 4;C1969024:Dilated cardiomyopathy 1X;C1969040:Autosomal recessive limb-girdle muscular dystrophy type 2M;C2751052:Muscular dystrophy-dystroglycanopathy (congenital without intellectual disability), type B4

Uncertain:1

Jun 11, 2024

Fulgent Genetics, Fulgent Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Cardiovascular phenotype

Uncertain:1

Dec 05, 2024

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The c.802G>T (p.V268L) alteration is located in exon 8 (coding exon 6) of the FKTN gene. This alteration results from a G to T substitution at nucleotide position 802, causing the valine (V) at amino acid position 268 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear.

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.089

BayesDel_addAF

Benign

-0.23

BayesDel_noAF

Benign

-0.39

CADD

Benign

(source)

DANN

Benign

0.94

DEOGEN2

Benign

0.18

Eigen

Benign

-0.31

Eigen_PC

Benign

-0.098

FATHMM_MKL

Uncertain

0.87

LIST_S2

Benign

0.69

M_CAP

Benign

0.032

MetaRNN

Benign

0.070

MetaSVM

Benign

-0.46

MutationAssessor

Benign

0.51

PhyloP100

0.78

PrimateAI

Benign

0.37

PROVEAN

Benign

-1.0

REVEL

Benign

0.20

Sift

Benign

0.75

Sift4G

Benign

0.62

Polyphen

0.0

Vest4

0.12

MutPred

0.29

Loss of catalytic residue at V268 (P = 0.0465)

MVP

0.69

MPC

0.081

ClinPred

0.41

GERP RS

4.2

Varity_R

0.10

gMVP

0.53

Mutation Taster

=84/16

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over