rs121912681

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1PM2PM4_SupportingPP5

The NM_000485.3(APRT):​c.521_523delTCT​(p.Phe174del) variant causes a disruptive inframe deletion change. The variant allele was found at a frequency of 0.0000632 in 1,613,428 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000062 ( 0 hom. )

Consequence

APRT
NM_000485.3 disruptive_inframe_deletion

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:6U:1

Conservation

PhyloP100: 4.52

Publications

2 publications found
Variant links:
Genes affected
APRT (HGNC:626): (adenine phosphoribosyltransferase) Adenine phosphoribosyltransferase belongs to the purine/pyrimidine phosphoribosyltransferase family. A conserved feature of this gene is the distribution of CpG dinucleotides. This enzyme catalyzes the formation of AMP and inorganic pyrophosphate from adenine and 5-phosphoribosyl-1-pyrophosphate (PRPP). It also produces adenine as a by-product of the polyamine biosynthesis pathway. A homozygous deficiency in this enzyme causes 2,8-dihydroxyadenine urolithiasis. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]
APRT Gene-Disease associations (from GenCC):
  • adenine phosphoribosyltransferase deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_000485.3
PM2
Very rare variant in population databases, with high coverage;
PM4
Nonframeshift variant in NON repetitive region in NM_000485.3. Strenght limited to Supporting due to length of the change: 1aa.
PP5
Variant 16-88809717-GAGA-G is Pathogenic according to our data. Variant chr16-88809717-GAGA-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 18294.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000485.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
APRT
NM_000485.3
MANE Select
c.521_523delTCTp.Phe174del
disruptive_inframe_deletion
Exon 5 of 5NP_000476.1
APRT
NM_001030018.2
c.401-14_401-12delTCT
intron
N/ANP_001025189.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
APRT
ENST00000378364.8
TSL:1 MANE Select
c.521_523delTCTp.Phe174del
disruptive_inframe_deletion
Exon 5 of 5ENSP00000367615.3
APRT
ENST00000563655.5
TSL:5
c.440_442delTCTp.Phe147del
disruptive_inframe_deletion
Exon 4 of 4ENSP00000456012.1
APRT
ENST00000567391.5
TSL:3
n.*195_*197delTCT
non_coding_transcript_exon
Exon 4 of 4ENSP00000457964.1

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152232
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.000121
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000384
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
GnomAD2 exomes
AF:
0.0000718
AC:
18
AN:
250756
AF XY:
0.0000737
show subpopulations
Gnomad AFR exome
AF:
0.000185
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000218
Gnomad FIN exome
AF:
0.0000925
Gnomad NFE exome
AF:
0.0000530
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000623
AC:
91
AN:
1461078
Hom.:
0
AF XY:
0.0000578
AC XY:
42
AN XY:
726832
show subpopulations
African (AFR)
AF:
0.000179
AC:
6
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.000101
AC:
4
AN:
39700
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86258
European-Finnish (FIN)
AF:
0.0000380
AC:
2
AN:
52652
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000647
AC:
72
AN:
1111980
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60384
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.457
Heterozygous variant carriers
0
6
12
17
23
29
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000722
AC:
11
AN:
152350
Hom.:
0
Cov.:
34
AF XY:
0.0000403
AC XY:
3
AN XY:
74500
show subpopulations
African (AFR)
AF:
0.000120
AC:
5
AN:
41572
American (AMR)
AF:
0.00
AC:
0
AN:
15310
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000385
AC:
2
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.520
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:
0.000216
Hom.:
0
Bravo
AF:
0.000125
Asia WGS
AF:
0.000577
AC:
2
AN:
3478
EpiCase
AF:
0.000218
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:6Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Adenine phosphoribosyltransferase deficiency Pathogenic:4Uncertain:1
Nov 01, 1987
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

Sep 23, 2024
3billion
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The variant is observed at an extremely low frequency in the gnomAD v4.0.0 dataset (total allele frequency: 0.006%). Predicted Consequence/Location: Inframe deletion located in a nonrepeat region: predicted to change the length of the protein and disrupt normal protein function. The variant has been reported at least twice as pathogenic with clinical assertions and evidence for the classification (ClinVar ID: VCV000018294 /PMID: 3680503). Therefore, this variant is classified as Likely pathogenic according to the recommendation of ACMG/AMP guideline.

Apr 04, 2024
Genomic Medicine Center of Excellence, King Faisal Specialist Hospital and Research Centre
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Sep 01, 2020
APRT Deficiency Research Program of the Rare Kidney Stone Consortium, Landspitali, National University Hospital of Iceland
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Feb 27, 2023
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

See cases Pathogenic:1
Feb 24, 2022
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: PS3, PM2, PM3, PM4

not provided Pathogenic:1
Aug 03, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is also known as c.517_519delTTC. For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 18294). This variant has been observed in individual(s) with adenine phosphoribosyltransferase deficiency (PMID: 3680503, 23430916). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. This variant is present in population databases (rs751152783, gnomAD 0.03%). This variant, c.521_523del, results in the deletion of 1 amino acid(s) of the APRT protein (p.Phe174del), but otherwise preserves the integrity of the reading frame.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
PhyloP100
4.5
Mutation Taster
=54/46
disease causing (ClinVar)

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: rs121912681; hg19: chr16-88876125; COSMIC: COSV99243598; COSMIC: COSV99243598; API