20-34295517-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_000687.4(AHCY):ā€‹c.97A>Gā€‹(p.Met33Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,952 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 (ā˜…).

Frequency

Genomes: š‘“ 0.0000066 ( 0 hom., cov: 32)
Exomes š‘“: 6.8e-7 ( 0 hom. )

Consequence

AHCY
NM_000687.4 missense

Scores

8
7
4

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.89
Variant links:
Genes affected
AHCY (HGNC:343): (adenosylhomocysteinase) S-adenosylhomocysteine hydrolase belongs to the adenosylhomocysteinase family. It catalyzes the reversible hydrolysis of S-adenosylhomocysteine (AdoHcy) to adenosine (Ado) and L-homocysteine (Hcy). Thus, it regulates the intracellular S-adenosylhomocysteine (SAH) concentration thought to be important for transmethylation reactions. Deficiency in this protein is one of the different causes of hypermethioninemia. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2009]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.906

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
AHCYNM_000687.4 linkuse as main transcriptc.97A>G p.Met33Val missense_variant 2/10 ENST00000217426.7

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
AHCYENST00000217426.7 linkuse as main transcriptc.97A>G p.Met33Val missense_variant 2/101 NM_000687.4 P1P23526-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152208
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
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461744
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
727182
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
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:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152208
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74360
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000207
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Hypermethioninemia with deficiency of S-adenosylhomocysteine hydrolase Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingInvitaeJan 13, 2018In summary, this variant is a novel missense change with uncertain impact on protein function. There is no indication that it causes disease, but the available evidence is currently insufficient to prove that conclusively. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a AHCY-related disease. This sequence change replaces methionine with valine at codon 33 of the AHCY protein (p.Met33Val). The methionine residue is highly conserved and there is a small physicochemical difference between methionine and valine. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Pathogenic
0.42
D
BayesDel_noAF
Pathogenic
0.36
CADD
Uncertain
24
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.83
D;.
Eigen
Benign
0.13
Eigen_PC
Benign
0.21
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.97
D;D
M_CAP
Uncertain
0.12
D
MetaRNN
Pathogenic
0.91
D;D
MetaSVM
Uncertain
-0.028
T
MutationAssessor
Pathogenic
3.3
M;.
MutationTaster
Benign
1.0
D;D
PrimateAI
Uncertain
0.61
T
PROVEAN
Uncertain
-3.3
D;D
REVEL
Pathogenic
0.79
Sift
Uncertain
0.011
D;D
Sift4G
Uncertain
0.019
D;D
Polyphen
0.037
B;.
Vest4
0.84
MutPred
0.73
Gain of helix (P = 0.0425);.;
MVP
0.93
MPC
0.64
ClinPred
0.98
D
GERP RS
5.0
Varity_R
0.62
gMVP
0.90

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: rs1555835400; hg19: chr20-32883323; API