1-1020216-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_198576.4(AGRN):c.44C>T(p.Pro15Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000215 in 1,396,032 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/19 in silico tools predict 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. P15R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 31)
  • Exomes 𝑓: 0.0000016 (0 hom.)
• Consequence: AGRN NM_198576.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.41

Genes affected

AGRN (HGNC:329): (agrin) This gene encodes one of several proteins that are critical in the development of the neuromuscular junction (NMJ), as identified in mouse knock-out studies. The encoded protein contains several laminin G, Kazal type serine protease inhibitor, and epidermal growth factor domains. Additional post-translational modifications occur to add glycosaminoglycans and disulfide bonds. In one family with congenital myasthenic syndrome affecting limb-girdle muscles, a mutation in this gene was found. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Mar 2015]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.093550116).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AGRN	NM_198576.4	c.44C>T	p.Pro15Leu	missense_variant	1/36	ENST00000379370.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AGRN	ENST00000379370.7	c.44C>T	p.Pro15Leu	missense_variant	1/36	1	NM_198576.4	P1
AGRN	ENST00000620552.4	c.-371C>T		5_prime_UTR_variant	1/39	5

Frequencies

GnomAD3 genomes AF: 0.00000660 AC: 1 AN: 151444 Hom.: 0 Cov.: 31

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: 0.0000148

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000393 AC: 2 AN: 50884 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 30530

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000260

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000161 AC: 2 AN: 1244588 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 611734

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000117

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 AF: 0.00000660 AC: 1 AN: 151444 Hom.: 0 Cov.: 31 AF XY: 0.0000135 AC XY: 1 AN XY: 73958

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000148

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Congenital myasthenic syndrome 8 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 31, 2021

This sequence change replaces proline with leucine at codon 15 of the AGRN protein (p.Pro15Leu). The proline residue is weakly conserved and there is a moderate physicochemical difference between proline and leucine. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the ExAC database. This variant has not been reported in the literature in individuals affected with AGRN-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0". The leucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect 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
BayesDel_addAF	Benign	-0.23	T
BayesDel_noAF	Benign	-0.26
Cadd	Benign	19
Dann	Benign	0.83
Eigen	Benign	-1.6
Eigen_PC	Benign	-1.5
FATHMM_MKL	Benign	0.0042	N
LIST_S2	Benign	0.41	T
M_CAP	Pathogenic	0.86	D
MetaRNN	Benign	0.094	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-1.8	N
MutationTaster	Benign	0.97	N
PrimateAI	Pathogenic	0.89	D
PROVEAN	Benign	0.98	N
REVEL	Benign	0.11
Sift	Benign	0.092	T
Sift4G	Benign	0.29	T
Vest4		0.17
MutPred		0.28		Loss of sheet (P = 0.0037);
MVP		0.54
MPC		0.44
ClinPred		0.089	T
GERP RS		0.71
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.4
gMVP		0.17

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: rs764659938; hg19: chr1-955596;