19-46755455-G-T

Variant names:

• chr19-46755455-G-T
• rs1308459613
• NM_024301.5:c.5G>T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_024301.5(FKRP):​c.5G>T​(p.Arg2Leu) variant causes a missense change. The variant allele was found at a frequency of 0.000000688 in 1,453,230 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 Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: FKRP NM_024301.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.13

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.887

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FKRP	NM_024301.5	c.5G>T	p.Arg2Leu	missense_variant	Exon 4 of 4	ENST00000318584.10	NP_077277.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FKRP	ENST00000318584.10	c.5G>T	p.Arg2Leu	missense_variant	Exon 4 of 4	1	NM_024301.5	ENSP00000326570.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.88e-7 AC: 1 AN: 1453230 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 723054

Gnomad4 AFR exome AF: 0.0000299

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Walker-Warburg congenital muscular dystrophy Uncertain:1

Dec 06, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 2 of the FKRP protein (p.Arg2Leu). This variant is not present in population databases (gnomAD no frequency). 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: 459240). Invitae Evidence 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 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	0.27
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.71	.;D;.;.;.;.;D;.;.;.;.;.;.;.;.;.;.;T
Eigen	Uncertain	0.54
Eigen_PC	Uncertain	0.50
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.85	T;.;T;T;T;T;T;T;T;T;T;T;T;T;T;T;.;T
M_CAP	Pathogenic	0.82	D
MetaRNN	Pathogenic	0.89	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Benign	1.7	.;L;.;.;.;.;L;.;.;.;.;.;.;.;.;.;.;.
PrimateAI	Pathogenic	0.86	D
PROVEAN	Uncertain	-3.8	.;D;.;.;.;.;D;.;.;.;.;.;.;.;.;.;.;.
REVEL	Pathogenic	0.83
Sift	Uncertain	0.0050	.;D;.;.;.;.;D;.;.;.;.;.;.;.;.;.;.;.
Sift4G	Pathogenic	0.0	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;.;D
Polyphen		1.0	.;D;.;.;.;.;D;.;.;.;.;.;.;.;.;.;.;.
Vest4		0.75, 0.69
MutPred		0.45		Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);Loss of MoRF binding (P = 0.0071);
MVP		0.98
MPC		1.8
ClinPred		0.98	D
GERP RS		3.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.43
gMVP		0.63

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: rs1308459613; hg19: chr19-47258712;