rs776639304

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM1BP4_Moderate

The NM_001079802.2(FKTN):​c.929A>G​(p.Asn310Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000049 in 1,591,508 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: š‘“ 0.000059 ( 0 hom., cov: 32)
Exomes š‘“: 0.000048 ( 0 hom. )

Consequence

FKTN
NM_001079802.2 missense

Scores

2
17

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1

Conservation

PhyloP100: 0.839

Publications

1 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_001079802.2
BP4
Computational evidence support a benign effect (MetaRNN=0.09504157).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FKTNNM_001079802.2 linkc.929A>G p.Asn310Ser missense_variant Exon 9 of 11 ENST00000357998.10 NP_001073270.1 O75072-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FKTNENST00000357998.10 linkc.929A>G p.Asn310Ser missense_variant Exon 9 of 11 5 NM_001079802.2 ENSP00000350687.6 O75072-1

Frequencies

GnomAD3 genomes
AF:
0.0000591
AC:
9
AN:
152240
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.000282
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000560
AC:
14
AN:
250202
AF XY:
0.0000517
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:
0.000139
Gnomad NFE exome
AF:
0.0000884
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000479
AC:
69
AN:
1439268
Hom.:
0
Cov.:
26
AF XY:
0.0000502
AC XY:
36
AN XY:
717586
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33042
American (AMR)
AF:
0.0000448
AC:
2
AN:
44634
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25948
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39546
South Asian (SAS)
AF:
0.0000117
AC:
1
AN:
85778
European-Finnish (FIN)
AF:
0.0000562
AC:
3
AN:
53374
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5492
European-Non Finnish (NFE)
AF:
0.0000568
AC:
62
AN:
1091810
Other (OTH)
AF:
0.0000168
AC:
1
AN:
59644
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.472
Heterozygous variant carriers
0
4
8
11
15
19
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:
0.0000591
AC:
9
AN:
152240
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74380
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41470
American (AMR)
AF:
0.0000654
AC:
1
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.000282
AC:
3
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68036
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
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000573
Hom.:
0
Bravo
AF:
0.0000378
ExAC
AF:
0.0000494
AC:
6
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Nov 28, 2022
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 14, 2020
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at a significant frequency in large population cohorts (Lek et al., 2016); In silico analysis supports that this missense variant does not alter protein structure/function; Missense variants in nearby residues reported in the Human Gene Mutation Database (Stenson et al., 2014); Has not been previously published as pathogenic or benign to our knowledge -

Walker-Warburg congenital muscular dystrophy Uncertain:2
Apr 22, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Oct 25, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 310 of the FKTN protein (p.Asn310Ser). This variant is present in population databases (rs776639304, gnomAD 0.01%). 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: 238269). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt FKTN protein function. 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. -

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;C4284790:Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A1 Uncertain:1
Nov 07, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Benign:1
Jul 11, 2023
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.045
BayesDel_addAF
Benign
-0.21
T
BayesDel_noAF
Benign
-0.34
CADD
Benign
11
DANN
Benign
0.70
DEOGEN2
Uncertain
0.50
T;T;.;.
Eigen
Benign
-0.52
Eigen_PC
Benign
-0.53
FATHMM_MKL
Benign
0.37
N
LIST_S2
Uncertain
0.89
.;D;.;D
M_CAP
Benign
0.0079
T
MetaRNN
Benign
0.095
T;T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-0.23
N;N;N;N
PhyloP100
0.84
PrimateAI
Benign
0.28
T
PROVEAN
Benign
-0.61
.;N;.;N
REVEL
Benign
0.23
Sift
Benign
0.36
.;T;.;T
Sift4G
Benign
0.45
T;T;T;T
Polyphen
0.0010
B;B;.;.
Vest4
0.051
MVP
0.66
MPC
0.067
ClinPred
0.025
T
GERP RS
-4.8
PromoterAI
0.011
Neutral
Varity_R
0.041
gMVP
0.16
Mutation Taster
=95/5
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: rs776639304; hg19: chr9-108380258; COSMIC: COSV56308397; COSMIC: COSV56308397; API