NM_000481.4:c.217C>T

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong

The NM_000481.4(AMT):​c.217C>T​(p.Arg73Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000322 in 1,613,720 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000032 ( 0 hom. )

Consequence

AMT
NM_000481.4 missense

Scores

12
6
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:12

Conservation

PhyloP100: 5.84
Variant links:
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]
NICN1 (HGNC:18317): (nicolin 1, tubulin polyglutamylase complex subunit) This protein encoded by this gene localizes to the nucleus and is expressed in numerous tissues including brain, testis, liver, and kidney. This refseq contains genomic sequence in its 3' UTR which is not supported by experimental evidence. Computer predictions indicate that this region of the 3' UTR contains hairpin-forming self-complementary sequence which is possibly excised after transcription. This gene has a pseudogene on chromosome X. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.986
PP5
Variant 3-49422145-G-A is Pathogenic according to our data. Variant chr3-49422145-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 56228.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr3-49422145-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
AMTNM_000481.4 linkc.217C>T p.Arg73Cys missense_variant Exon 2 of 9 ENST00000273588.9 NP_000472.2 P48728-1A0A024R2U7
NICN1NM_032316.3 linkc.*2688C>T downstream_gene_variant ENST00000273598.8 NP_115692.1 Q9BSH3-1B2R7Q3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
AMTENST00000273588.9 linkc.217C>T p.Arg73Cys missense_variant Exon 2 of 9 1 NM_000481.4 ENSP00000273588.3 P48728-1
ENSG00000283189ENST00000636166.1 linkc.496-573C>T intron_variant Intron 4 of 10 5 ENSP00000490106.1 A0A1B0GUH1
NICN1ENST00000273598.8 linkc.*2688C>T downstream_gene_variant 1 NM_032316.3 ENSP00000273598.4 Q9BSH3-1

Frequencies

GnomAD3 genomes
AF:
0.0000328
AC:
5
AN:
152212
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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
GnomAD3 exomes
AF:
0.0000358
AC:
9
AN:
251240
Hom.:
0
AF XY:
0.0000294
AC XY:
4
AN XY:
135916
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000616
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000322
AC:
47
AN:
1461508
Hom.:
0
Cov.:
31
AF XY:
0.0000316
AC XY:
23
AN XY:
727052
show subpopulations
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:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000387
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000328
AC:
5
AN:
152212
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74366
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000655
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000588
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000557
Hom.:
0
Bravo
AF:
0.0000340
ExAC
AF:
0.0000412
AC:
5
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000119

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:12
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Glycine encephalopathy Pathogenic:7
Dec 16, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 73 of the AMT protein (p.Arg73Cys). This variant is present in population databases (rs386833679, gnomAD 0.006%). This missense change has been observed in individual(s) with glycine encephalopathy (PMID: 16450403, 27362913). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 56228). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt AMT protein function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -

Mar 12, 2021
Centre for Inherited Metabolic Diseases, Karolinska University Hospital
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Juha Muilu Group; Institute for Molecular Medicine Finland (FIMM)
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Sep 16, 2020
Natera, Inc.
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Mar 17, 2017
Counsyl
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Apr 02, 2020
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant was classified as: Likely pathogenic. The following ACMG criteria were applied in classifying this variant: PM3_STR,PM2,PP3. -

Dec 01, 2021
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: AMT c.217C>T (p.Arg73Cys) results in a non-conservative amino acid change located in the Aminomethyltransferase, folate-binding domain (IPR006222) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 3.6e-05 in 251240 control chromosomes (gnomAD). c.217C>T has been reported in the literature in multiple compound heterozygous and homozygous individuals affected with Glycine Encephalopathy (Non-Ketotic Hyperglycinemia) (example: Kure_2006, Coughlin_2017, Isik_2019, Stranneheim_2021). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Six ClinVar submitters have assessed this variant after 2014: four classified the variant as likely pathogenic and two have classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Glycine encephalopathy 2 Pathogenic:2
Feb 05, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Feb 01, 2024
Laboratory of Medical Genetics, National & Kapodistrian University of Athens
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: curation

- -

See cases Pathogenic:1
Dec 26, 2019
Laboratorio de Genetica e Diagnostico Molecular, Hospital Israelita Albert Einstein
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

ACMG classification criteria: PS4, PM2, PM3, PP3 -

not provided Pathogenic:1
Sep 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

AMT: PM3:Very Strong, PM2 -

Glycine encephalopathy 1 Pathogenic:1
Feb 05, 2024
Baylor Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.75
BayesDel_addAF
Pathogenic
0.34
D
BayesDel_noAF
Pathogenic
0.42
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.94
D;T;.;.;D;D;T;D;.;.;D;D
Eigen
Uncertain
0.39
Eigen_PC
Uncertain
0.34
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Uncertain
0.97
D;D;D;D;D;D;D;D;D;D;D;D
M_CAP
Pathogenic
0.34
D
MetaRNN
Pathogenic
0.99
D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.64
D
MutationAssessor
Pathogenic
3.7
H;.;H;H;.;.;.;.;.;.;.;.
PrimateAI
Uncertain
0.60
T
PROVEAN
Pathogenic
-7.0
D;.;D;D;.;.;.;.;.;.;.;.
REVEL
Pathogenic
0.82
Sift
Pathogenic
0.0
D;.;D;D;.;.;.;.;.;.;.;.
Sift4G
Pathogenic
0.0
D;.;D;D;.;.;.;.;.;.;.;.
Polyphen
1.0
D;.;.;.;.;.;.;.;.;.;.;.
Vest4
0.99
MutPred
0.96
Loss of disorder (P = 0.0222);Loss of disorder (P = 0.0222);Loss of disorder (P = 0.0222);Loss of disorder (P = 0.0222);.;Loss of disorder (P = 0.0222);.;Loss of disorder (P = 0.0222);.;Loss of disorder (P = 0.0222);.;Loss of disorder (P = 0.0222);
MVP
0.95
MPC
0.94
ClinPred
0.99
D
GERP RS
4.5
Varity_R
0.93
gMVP
0.89

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs386833679; hg19: chr3-49459578; API