3-49422391-CG-CGGGG

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2PM4_Supporting

The NM_000481.4(AMT):​c.57_59dupCCC​(p.Pro20dup) variant causes a disruptive inframe insertion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,704 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. P20P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

AMT
NM_000481.4 disruptive_inframe_insertion

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, single submitter U:2

Conservation

PhyloP100: -0.545

Publications

1 publications found
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 was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM4
Nonframeshift variant in NON repetitive region in NM_000481.4. Strenght limited to Supporting due to length of the change: 1aa.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
AMTNM_000481.4 linkc.57_59dupCCC p.Pro20dup disruptive_inframe_insertion Exon 1 of 9 ENST00000273588.9 NP_000472.2 P48728-1A0A024R2U7
NICN1NM_032316.3 linkc.*2439_*2441dupCCC 3_prime_UTR_variant Exon 6 of 6 ENST00000273598.8 NP_115692.1 Q9BSH3-1B2R7Q3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
AMTENST00000273588.9 linkc.57_59dupCCC p.Pro20dup disruptive_inframe_insertion Exon 1 of 9 1 NM_000481.4 ENSP00000273588.3 P48728-1
NICN1ENST00000273598.8 linkc.*2439_*2441dupCCC 3_prime_UTR_variant Exon 6 of 6 1 NM_032316.3 ENSP00000273598.4 Q9BSH3-1
ENSG00000283189ENST00000636166.1 linkc.496-822_496-820dupCCC intron_variant Intron 4 of 10 5 ENSP00000490106.1 A0A1B0GUH1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152084
Hom.:
0
Cov.:
32
show subpopulations
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:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
250880
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS 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:
0.00000479
AC:
7
AN:
1461620
Hom.:
0
Cov.:
36
AF XY:
0.00000550
AC XY:
4
AN XY:
727112
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000812
AC:
7
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53186
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111986
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152084
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74288
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41422
American (AMR)
AF:
0.00
AC:
0
AN:
15262
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68010
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Glycine encephalopathy Uncertain:1
Dec 02, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant, c.57_59dup, results in the insertion of 1 amino acid(s) of the AMT protein (p.Pro20dup), but otherwise preserves the integrity of the reading frame. This variant is present in population databases (rs770510324, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with AMT-related conditions. ClinVar contains an entry for this variant (Variation ID: 556727). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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. -

Glycine encephalopathy 1 Uncertain:1
Feb 15, 2018
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
-0.55
Mutation Taster
=82/18
polymorphism

Splicing

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

Publications

Other links and lift over

dbSNP: rs386833686; hg19: chr3-49459824; API