6-135431299-G-C

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_001134831.2(AHI1):​c.2282C>G​(p.Ser761*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000139 in 1,444,020 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 Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. S761S) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

AHI1
NM_001134831.2 stop_gained

Scores

5
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:2

Conservation

PhyloP100: 6.22

Publications

4 publications found
Variant links:
Genes affected
AHI1 (HGNC:21575): (Abelson helper integration site 1) This gene is apparently required for both cerebellar and cortical development in humans. This gene mutations cause specific forms of Joubert syndrome-related disorders. Joubert syndrome (JS) is a recessively inherited developmental brain disorder with several identified causative chromosomal loci. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Oct 2008]
AHI1 Gene-Disease associations (from GenCC):
  • Joubert syndrome 3
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Laboratory for Molecular Medicine, Ambry Genetics
  • Joubert syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Joubert syndrome with ocular defect
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • retinitis pigmentosa
    Inheritance: AR, AD Classification: SUPPORTIVE, LIMITED Submitted by: Ambry Genetics, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 6-135431299-G-C is Pathogenic according to our data. Variant chr6-135431299-G-C is described in ClinVar as Pathogenic. ClinVar VariationId is 2716958.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001134831.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
AHI1
NM_001134831.2
MANE Select
c.2282C>Gp.Ser761*
stop_gained
Exon 17 of 29NP_001128303.1
AHI1
NM_001134830.2
c.2282C>Gp.Ser761*
stop_gained
Exon 15 of 27NP_001128302.1
AHI1
NM_001350503.2
c.2282C>Gp.Ser761*
stop_gained
Exon 17 of 29NP_001337432.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
AHI1
ENST00000265602.11
TSL:1 MANE Select
c.2282C>Gp.Ser761*
stop_gained
Exon 17 of 29ENSP00000265602.6
AHI1
ENST00000367800.8
TSL:1
c.2282C>Gp.Ser761*
stop_gained
Exon 15 of 27ENSP00000356774.4
AHI1
ENST00000457866.6
TSL:1
c.2282C>Gp.Ser761*
stop_gained
Exon 16 of 28ENSP00000388650.2

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000848
AC:
2
AN:
235904
AF XY:
0.0000157
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000601
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:
0.00000139
AC:
2
AN:
1444020
Hom.:
0
Cov.:
27
AF XY:
0.00000279
AC XY:
2
AN XY:
718022
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33148
American (AMR)
AF:
0.0000456
AC:
2
AN:
43828
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25830
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39298
South Asian (SAS)
AF:
0.00
AC:
0
AN:
84014
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52890
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5718
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1099566
Other (OTH)
AF:
0.00
AC:
0
AN:
59728
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
1
1
2
2
3
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
Cov.:
32
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Joubert syndrome Pathogenic:1
Dec 03, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Ser761*) in the AHI1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in AHI1 are known to be pathogenic (PMID: 15322546, 16453322, 28442542, 29186038). This variant is present in population databases (no rsID available, gnomAD 0.009%). This variant has not been reported in the literature in individuals affected with AHI1-related conditions. ClinVar contains an entry for this variant (Variation ID: 2716958). For these reasons, this variant has been classified as Pathogenic.

Joubert syndrome 3 Pathogenic:1
Oct 06, 2023
Illumina Laboratory Services, Illumina
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The AHI1 c.2282C>G p.(Ser761Ter) nonsense variant results in the loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay. To our knowledge, the c.2282C>G variant has not been reported in the peer-reviewed literature and is not observed at a significant frequency in version 2.1.1 or version 3.1.2 of the Genome Aggregation Database. This variant was identified in trans with a variant of uncertain significance in this proband with a phenotype consistent with Joubert syndrome. Based on the available evidence, the c.2282C>G p.(Ser761Ter) variant is classified as pathogenic for Joubert syndrome.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.49
D
BayesDel_noAF
Pathogenic
0.65
CADD
Pathogenic
42
DANN
Uncertain
1.0
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.98
FATHMM_MKL
Pathogenic
0.99
D
PhyloP100
6.2
Vest4
0.99
ClinPred
1.0
D
GERP RS
5.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Mutation Taster
=1/199
disease causing (fs/PTC)

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: rs794727174; hg19: chr6-135752437; API