rs775047750

chr1-1053806-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_198576.4(AGRN):c.5705C>T(p.Thr1902Met) variant causes a missense change. The variant allele was found at a frequency of 0.00000683 in 1,611,072 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 (★). Synonymous variant affecting the same amino acid position (i.e. T1902T) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: AGRN NM_198576.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.76

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 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.804

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AGRN	NM_198576.4	c.5705C>T	p.Thr1902Met	missense_variant	34/36	ENST00000379370.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AGRN	ENST00000379370.7	c.5705C>T	p.Thr1902Met	missense_variant	34/36	1	NM_198576.4	P1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152256 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000818 AC: 2 AN: 244450 Hom.: 0 AF XY: 0.00000753 AC XY: 1 AN XY: 132726

Gnomad AFR exome AF: 0.0000642

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: 0.00000906

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000617 AC: 9 AN: 1458816 Hom.: 0 Cov.: 35 AF XY: 0.00000414 AC XY: 3 AN XY: 725504

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: 0.00000630

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152256 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74378

Gnomad4 AFR AF: 0.0000241

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: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000343 Hom.: 0

Bravo AF: 0.0000529

ExAC AF: 0.00000825 AC: 1

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 16, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0". The methionine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. ClinVar contains an entry for this variant (Variation ID: 582978). This variant has not been reported in the literature in individuals affected with AGRN-related conditions. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 1902 of the AGRN protein (p.Thr1902Met). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.034	T
BayesDel_noAF	Benign	-0.29
Cadd	Uncertain	25
Dann	Uncertain	1.0
Eigen	Uncertain	0.30
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.92	D;D
M_CAP	Uncertain	0.19	D
MetaRNN	Pathogenic	0.80	D;D
MetaSVM	Benign	-0.38	T
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.59	T
PROVEAN	Uncertain	-3.1	D;.
REVEL	Uncertain	0.40
Sift	Benign	0.035	D;.
Sift4G	Uncertain	0.036	D;D
Vest4		0.74
MVP		0.77
MPC		0.50
ClinPred		0.87	D
GERP RS		2.9
RBP_binding_hub_radar		0.97
RBP_regulation_power_radar		2.1
gMVP		0.59

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: rs775047750; hg19: chr1-989186;