rs769568971

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM2PM5BP4

The NM_024301.5(FKRP):​c.1270A>C​(p.Asn424His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000434 in 1,611,674 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. N424?) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000042 ( 0 hom. )

Consequence

FKRP
NM_024301.5 missense

Scores

3
7
9

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:10

Conservation

PhyloP100: 3.48
Variant links:
Genes affected
FKRP (HGNC:17997): (fukutin related protein) This gene encodes a protein which is targeted to the medial Golgi apparatus and is necessary for posttranslational modification of dystroglycan. Mutations in this gene have been associated with congenital muscular dystrophy, cognitive disability, and cerebellar cysts. Several alternatively spliced transcript variants of this gene have been described, but the full-length nature of some of these variants has not been determined. [provided by RefSeq, Oct 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr19-46756719-CAA-CT is described in Lovd as [Pathogenic].
BP4
Computational evidence support a benign effect (MetaRNN=0.38109475).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FKRPNM_024301.5 linkc.1270A>C p.Asn424His missense_variant Exon 4 of 4 ENST00000318584.10 NP_077277.1 Q9H9S5A0A024R0R7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FKRPENST00000318584.10 linkc.1270A>C p.Asn424His missense_variant Exon 4 of 4 1 NM_024301.5 ENSP00000326570.4 Q9H9S5
FKRPENST00000391909.7 linkc.1270A>C p.Asn424His missense_variant Exon 4 of 4 2 ENSP00000375776.2 Q9H9S5
FKRPENST00000597339.5 linkn.247-5113A>C intron_variant Intron 3 of 3 5
FKRPENST00000600646.5 linkn.247+8055A>C intron_variant Intron 3 of 3 3

Frequencies

GnomAD3 genomes
AF:
0.0000591
AC:
9
AN:
152212
Hom.:
0
Cov.:
33
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:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000118
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000327
AC:
8
AN:
244516
Hom.:
0
AF XY:
0.0000378
AC XY:
5
AN XY:
132446
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000723
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000418
AC:
61
AN:
1459462
Hom.:
0
Cov.:
32
AF XY:
0.0000400
AC XY:
29
AN XY:
725820
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000504
Gnomad4 OTH exome
AF:
0.0000663
GnomAD4 genome
AF:
0.0000591
AC:
9
AN:
152212
Hom.:
0
Cov.:
33
AF XY:
0.0000538
AC XY:
4
AN XY:
74370
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.000118
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000127
Hom.:
0
Bravo
AF:
0.0000718
ExAC
AF:
0.0000330
AC:
4

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:10
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:4
Feb 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

FKRP: PM2 -

Dec 14, 2016
Eurofins Ntd Llc (ga)
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Aug 23, 2017
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

A variant of uncertain significance has been identified in the FKRP gene. The N424H variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. The N424H variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016). The N424H variant is a semi-conservative amino acid substitution, which may impact secondary protein structure as these residues differ in some properties. In silico analysis predicts this variant is probably damaging to the protein structure/function. However, this substitution occurs at a position that is not conserved. Therefore, based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant. -

Jul 27, 2022
Revvity Omics, Revvity
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2I;C1847759:Muscular dystrophy-dystroglycanopathy type B5;C3150413:Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A5;C4284790:Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A1 Uncertain:1
Jul 01, 2021
Fulgent Genetics, Fulgent Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2I Uncertain:1
Jan 17, 2020
Natera, Inc.
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Muscular dystrophy-dystroglycanopathy type B5 Uncertain:1
Oct 24, 2018
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant was classified as: Uncertain significance. The available evidence favors the pathogenic nature of this variant, however the currently available data is insufficient to conclusively support its pathogenic nature. Thus this variant is classified as Uncertain significance - favor pathogenic. The following ACMG criteria were applied in classifying this variant: PM2,PP3. -

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A5 Uncertain:1
Jul 02, 2020
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.3, this variant is classified as 3B-VUS. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with muscular dystrophy-dystroglycanopathy (OMIM). 0106 - This gene is associated with autosomal recessive disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from asparagine to histidine (exon 4). (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD v3 <0.01 for a recessive condition (7 heterozygotes, 0 homozygotes). (SP) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (v3) (2 heterozygotes, 0 homozygotes). (I) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0604 - Variant is not located in an established domain, motif, hotspot or informative constraint region. (I) 0705 - No comparable missense variants have previous evidence for pathogenicity. (I) 0809 - Previous evidence of pathogenicity for this variant is inconclusive. The variant has been classified as a Variant of Uncertain Significance (ClinVar). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1206 - This variant has been shown to be paternally inherited (by trio analysis). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Cardiovascular phenotype Uncertain:1
Jan 29, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.N424H variant (also known as c.1270A>C), located in coding exon 1 of the FKRP gene, results from an A to C substitution at nucleotide position 1270. The asparagine at codon 424 is replaced by histidine, an amino acid with similar properties. This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Walker-Warburg congenital muscular dystrophy Uncertain:1
Oct 17, 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 histidine, which is basic and polar, at codon 424 of the FKRP protein (p.Asn424His). This variant is present in population databases (rs769568971, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with FKRP-related conditions. ClinVar contains an entry for this variant (Variation ID: 449685). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on FKRP 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.13
BayesDel_addAF
Benign
-0.076
T
BayesDel_noAF
Benign
-0.16
CADD
Pathogenic
26
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.81
D;D
Eigen
Benign
-0.25
Eigen_PC
Benign
-0.14
FATHMM_MKL
Benign
0.74
D
LIST_S2
Benign
0.72
.;T
M_CAP
Pathogenic
0.41
D
MetaRNN
Benign
0.38
T;T
MetaSVM
Pathogenic
0.93
D
MutationAssessor
Uncertain
2.1
M;M
PrimateAI
Uncertain
0.69
T
PROVEAN
Uncertain
-3.3
D;D
REVEL
Uncertain
0.49
Sift
Uncertain
0.0050
D;D
Sift4G
Uncertain
0.012
D;D
Polyphen
0.0030
B;B
Vest4
0.42
MutPred
0.61
Gain of sheet (P = 0.0221);Gain of sheet (P = 0.0221);
MVP
0.88
MPC
1.7
ClinPred
0.35
T
GERP RS
3.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.50
gMVP
0.56

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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs769568971; hg19: chr19-47259977; API