NM_024301.5:c.446G>A

Variant names:

• chr19-46755896-G-A
• rs1449983261
• NM_024301.5:c.446G>A

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_024301.5(FKRP):​c.446G>A​(p.Arg149His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000066 in 1,514,872 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 0.000026 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000044 (0 hom.)
• Consequence: FKRP NM_024301.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 1.93
• Publications: 0 publications found

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]

FKRP Gene-Disease associations (from GenCC):

• autosomal recessive limb-girdle muscular dystrophy type 2I

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Laboratory for Molecular Medicine, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A5

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Genomics England PanelApp, Ambry Genetics, G2P
• muscular dystrophy-dystroglycanopathy type B5

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Myriad Women’s Health
• myopathy caused by variation in FKRP

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• congenital muscular dystrophy with cerebellar involvement

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• congenital muscular dystrophy with intellectual disability

  Inheritance: AR 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

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 46 curated pathogenic missense variants (we use a threshold of 10). The gene has 2 curated benign missense variants. Gene score misZ: 1.8498 (below the threshold of 3.09). Trascript score misZ: -2.4986 (below the threshold of 3.09). GenCC associations: The gene is linked to autosomal recessive limb-girdle muscular dystrophy type 2I, muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A5, congenital muscular dystrophy with intellectual disability, muscular dystrophy-dystroglycanopathy, type A, muscle-eye-brain disease, congenital muscular dystrophy with cerebellar involvement, myopathy caused by variation in FKRP, muscular dystrophy-dystroglycanopathy type B5, congenital muscular dystrophy without intellectual disability.
• BP4: Computational evidence support a benign effect (MetaRNN=0.2945698).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_024301.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FKRP	NM_024301.5	MANE Select	c.446G>A	p.Arg149His	missense	Exon 4 of 4	NP_077277.1
	FKRP	NM_001039885.3		c.446G>A	p.Arg149His	missense	Exon 4 of 4	NP_001034974.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FKRP	ENST00000318584.10	TSL:1 MANE Select	c.446G>A	p.Arg149His	missense	Exon 4 of 4	ENSP00000326570.4
	FKRP	ENST00000391909.7	TSL:2	c.446G>A	p.Arg149His	missense	Exon 4 of 4	ENSP00000375776.2
	FKRP	ENST00000908841.1		c.446G>A	p.Arg149His	missense	Exon 3 of 3	ENSP00000578900.1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152220 Hom.: 0 Cov.: 33

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: 0.0000588

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00 AC: 0 AN: 114180 AF XY: 0.00

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: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000440 AC: 6 AN: 1362652 Hom.: 0 Cov.: 32 AF XY: 0.00000596 AC XY: 4 AN XY: 670816

African (AFR) AF: 0.00 AC: 0 AN: 30548

American (AMR) AF: 0.00 AC: 0 AN: 32546

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 23734

East Asian (EAS) AF: 0.00 AC: 0 AN: 35190

South Asian (SAS) AF: 0.00 AC: 0 AN: 76274

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 33676

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5458

European-Non Finnish (NFE) AF: 0.00000562 AC: 6 AN: 1068352

Other (OTH) AF: 0.00 AC: 0 AN: 56874

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152220 Hom.: 0 Cov.: 33 AF XY: 0.0000269 AC XY: 2 AN XY: 74362

African (AFR) AF: 0.00 AC: 0 AN: 41466

American (AMR) AF: 0.00 AC: 0 AN: 15288

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5194

South Asian (SAS) AF: 0.00 AC: 0 AN: 4838

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10622

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.0000588 AC: 4 AN: 68022

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000189

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Autosomal recessive limb-girdle muscular dystrophy type 2I (1)
-	1	-	Cardiovascular phenotype (1)
-	1	-	Walker-Warburg congenital muscular dystrophy (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Uncertain	0.063	T
BayesDel_noAF	Benign	-0.15
CADD	Benign	19
DANN	Benign	0.95
DEOGEN2	Benign	0.24	T
Eigen	Benign	-0.50
Eigen_PC	Benign	-0.52
FATHMM_MKL	Benign	0.11	N
LIST_S2	Benign	0.78	T
M_CAP	Uncertain	0.26	D
MetaRNN	Benign	0.29	T
MetaSVM	Uncertain	0.65	D
MutationAssessor	Benign	0.55	N
PhyloP100		1.9
PrimateAI	Pathogenic	0.85	D
PROVEAN	Benign	-0.57	N
REVEL	Uncertain	0.35
Sift	Benign	0.18	T
Sift4G	Uncertain	0.037	D
Polyphen		0.78	P
Vest4		0.078
MutPred		0.32		Loss of MoRF binding (P = 0.0166)
MVP		0.98
MPC		1.2
ClinPred		0.22	T
GERP RS		1.2
Varity_R		0.18
gMVP		0.46
Mutation Taster		=81/19	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

Other links and lift over

dbSNP: rs1449983261; hg19: chr19-47259153; COSMIC: COSV105897086; COSMIC: COSV105897086;