3-49718515-C-G

Variant names:

• chr3-49718515-C-G
• rs138809316
• NM_198722.3:c.951G>C

Variant summary

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

The NM_198722.3(AMIGO3):​c.951G>C​(p.Glu317Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,460,816 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: AMIGO3 NM_198722.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.893
• Publications: 0 publications found

Genes affected

AMIGO3 (HGNC:24075): (adhesion molecule with Ig like domain 3) Predicted to be involved in brain development and heterophilic cell-cell adhesion via plasma membrane cell adhesion molecules. Predicted to act upstream of or within positive regulation of synapse assembly. Predicted to be integral component of membrane. [provided by Alliance of Genome Resources, Apr 2022]

RNF123 (HGNC:21148): (ring finger protein 123) The protein encoded by this gene contains a C-terminal RING finger domain, a motif present in a variety of functionally distinct proteins and known to be involved in protein-protein and protein-DNA interactions, and an N-terminal SPRY domain. This protein displays E3 ubiquitin ligase activity toward the cyclin-dependent kinase inhibitor 1B which is also known as p27 or KIP1. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2016]

GMPPB (HGNC:22932): (GDP-mannose pyrophosphorylase B) This gene is thought to encode a GDP-mannose pyrophosphorylase. The encoded protein catalyzes the conversion of mannose-1-phosphate and GTP to GDP-mannose, a reaction involved in the production of N-linked oligosaccharides. Alternatively spliced transcript variants encoding distinct isoforms have been described. [provided by RefSeq, Jan 2009]

GMPPB Gene-Disease associations (from GenCC):

• muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A14

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• myopathy caused by variation in GMPPB

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• autosomal recessive limb-girdle muscular dystrophy type 2T

  Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae)
• congenital myasthenic syndrome

  Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp
• 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 myasthenic syndromes with glycosylation defect

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• muscle-eye-brain disease

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.3975082).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_198722.3. 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
	AMIGO3	NM_198722.3	MANE Select	c.951G>C	p.Glu317Asp	missense	Exon 1 of 1	NP_942015.1	Q86WK7
	RNF123	NM_022064.5	MANE Select	c.3501-1996C>G		intron	N/A	NP_071347.2
	RNF123	NR_135218.2		n.3827-1996C>G		intron	N/A

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	AMIGO3	ENST00000320431.8	TSL:6 MANE Select	c.951G>C	p.Glu317Asp	missense	Exon 1 of 1	ENSP00000323096.7	Q86WK7
	RNF123	ENST00000327697.11	TSL:1 MANE Select	c.3501-1996C>G		intron	N/A	ENSP00000328287.6	Q5XPI4-1
	RNF123	ENST00000457726.5	TSL:1	n.*1575-1996C>G		intron	N/A	ENSP00000394369.1	C9JS59

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460816 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 726758

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44710

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26112

East Asian (EAS) AF: 0.00 AC: 0 AN: 39694

South Asian (SAS) AF: 0.00 AC: 0 AN: 86250

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52516

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111918

Other (OTH) AF: 0.00 AC: 0 AN: 60374

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.27
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.070
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Benign	0.035	T
Eigen	Uncertain	0.24
Eigen_PC	Benign	0.17
FATHMM_MKL	Uncertain	0.80	D
LIST_S2	Benign	0.55	T
M_CAP	Uncertain	0.19	D
MetaRNN	Benign	0.40	T
MetaSVM	Uncertain	-0.069	T
MutationAssessor	Uncertain	2.7	M
PhyloP100		0.89
PrimateAI	Uncertain	0.62	T
PROVEAN	Benign	-1.5	N
REVEL	Uncertain	0.45
Sift	Benign	0.031	D
Sift4G	Benign	0.067	T
Polyphen		1.0	D
Vest4		0.28
MutPred		0.23		Gain of relative solvent accessibility (P = 0.1894)
MVP		0.90
ClinPred		0.93	D
GERP RS		3.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.27
gMVP		0.78
Mutation Taster		=81/19	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs138809316; hg19: chr3-49755948;