20-34280413-A-G

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBS1_Supporting

The NM_000687.4(AHCY):​c.*621T>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000591 in 152,252 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

AHCY
NM_000687.4 3_prime_UTR

Scores

2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.179

Publications

0 publications found
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]
AHCY Gene-Disease associations (from GenCC):
  • hypermethioninemia with deficiency of S-adenosylhomocysteine hydrolase
    Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.74).
BS1
Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.0000591 (9/152252) while in subpopulation EAS AF = 0.000772 (4/5182). AF 95% confidence interval is 0.000263. There are 0 homozygotes in GnomAd4. There are 6 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
AHCYNM_000687.4 linkc.*621T>C 3_prime_UTR_variant Exon 10 of 10 ENST00000217426.7 NP_000678.1 P23526-1A0A384MTQ3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
AHCYENST00000217426.7 linkc.*621T>C 3_prime_UTR_variant Exon 10 of 10 1 NM_000687.4 ENSP00000217426.2 P23526-1
AHCYENST00000480653.5 linkn.2068T>C non_coding_transcript_exon_variant Exon 9 of 9 2
AHCYENST00000538132.1 linkc.*621T>C 3_prime_UTR_variant Exon 10 of 10 2 ENSP00000442820.1 P23526-2
ENSG00000250917ENST00000512005.1 linkn.147+614T>C intron_variant Intron 1 of 2 3

Frequencies

GnomAD3 genomes
AF:
0.0000592
AC:
9
AN:
152134
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:
0.000770
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.000283
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.000478
GnomAD4 exome
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
1736
Hom.:
0
Cov.:
0
AF XY:
0.00
AC XY:
0
AN XY:
868
African (AFR)
AF:
0.00
AC:
0
AN:
6
American (AMR)
AF:
0.00
AC:
0
AN:
344
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
8
East Asian (EAS)
AF:
0.00
AC:
0
AN:
36
South Asian (SAS)
AF:
0.00
AC:
0
AN:
98
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
4
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
2
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1180
Other (OTH)
AF:
0.00
AC:
0
AN:
58
GnomAD4 genome
AF:
0.0000591
AC:
9
AN:
152252
Hom.:
0
Cov.:
32
AF XY:
0.0000806
AC XY:
6
AN XY:
74446
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41546
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000772
AC:
4
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.000283
AC:
3
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68018
Other (OTH)
AF:
0.000473
AC:
1
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.519
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

Genome 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
Alfa
AF:
0.0000540
Hom.:
0
Bravo
AF:
0.0000151
Asia WGS
AF:
0.000577
AC:
2
AN:
3478

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
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.74
CADD
Benign
2.4
DANN
Benign
0.77
PhyloP100
0.18
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
2.1

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs886056634; hg19: chr20-32868219; API