chr3-49419784-T-C

Position:

• chr3-49419784-T-C

Variant summary

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

The NM_000481.4(AMT):​c.476A>G​(p.Lys159Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,613,952 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/23 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: AMT NM_000481.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 1.12

Genes affected

AMT (HGNC:473): (aminomethyltransferase) This gene encodes one of four critical components of the glycine cleavage system. Mutations in this gene have been associated with glycine encephalopathy. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Sep 2011]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
AMT	NM_000481.4	c.476A>G	p.Lys159Arg	missense_variant	5/9	ENST00000273588.9	NP_000472.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
AMT	ENST00000273588.9	c.476A>G	p.Lys159Arg	missense_variant	5/9	1	NM_000481.4	ENSP00000273588	P1

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 152090 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461862 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727228

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

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: 0.0000132 AC: 2 AN: 152090 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74294

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.000131

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Non-ketotic hyperglycinemia Uncertain:2

Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Aug 24, 2021	This sequence change replaces lysine with arginine at codon 159 of the AMT protein (p.Lys159Arg). The lysine residue is moderately conserved and there is a small physicochemical difference between lysine and arginine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with AMT-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The arginine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. 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	0.072
BayesDel_addAF	Benign	-0.060	T
BayesDel_noAF	Benign	-0.32
CADD	Uncertain	24
DANN	Benign	0.71
DEOGEN2	Uncertain	0.43	T;.;.;T;T;T;T;.;.;T;T;.;.;.
Eigen	Benign	-0.53
Eigen_PC	Benign	-0.36
FATHMM_MKL	Benign	0.69	D
LIST_S2	Benign	0.81	T;T;T;T;T;T;T;T;T;T;T;T;T;T
M_CAP	Benign	0.041	D
MetaRNN	Benign	0.14	T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.75	T
MutationAssessor	Benign	-0.22	N;N;.;.;.;.;.;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Benign	0.37	T
PROVEAN	Benign	-0.57	N;N;N;.;.;.;.;.;.;.;.;.;.;.
REVEL	Benign	0.27
Sift	Benign	0.57	T;T;T;.;.;.;.;.;.;.;.;.;.;.
Sift4G	Benign	0.50	T;T;T;.;.;.;.;.;.;.;.;.;.;.
Polyphen		0.0020	B;.;.;.;.;.;.;.;.;.;.;.;.;.
Vest4		0.16
MutPred		0.47		Loss of ubiquitination at K159 (P = 0.0309);Loss of ubiquitination at K159 (P = 0.0309);.;.;Loss of ubiquitination at K159 (P = 0.0309);.;Loss of ubiquitination at K159 (P = 0.0309);.;.;.;.;.;.;.;
MVP		0.82
MPC		0.17
ClinPred		0.22	T
GERP RS		4.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.13
gMVP		0.43

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.38		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.38		Position offset: 44

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1553638556; hg19: chr3-49457217;