chr6-135431282-C-A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM1BP4_Strong

The NM_001134831.2(AHI1):​c.2299G>T​(p.Val767Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000311 in 1,607,980 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000034 ( 0 hom. )

Consequence

AHI1
NM_001134831.2 missense

Scores

1
18

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 0.307

Publications

1 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: Likely_benign. The variant received -2 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 7 uncertain in NM_001134831.2
BP4
Computational evidence support a benign effect (MetaRNN=0.03901565).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
AHI1NM_001134831.2 linkc.2299G>T p.Val767Leu missense_variant Exon 17 of 29 ENST00000265602.11 NP_001128303.1 Q8N157-1Q8NER0

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
AHI1ENST00000265602.11 linkc.2299G>T p.Val767Leu missense_variant Exon 17 of 29 1 NM_001134831.2 ENSP00000265602.6 Q8N157-1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
151992
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000370
AC:
9
AN:
242950
AF XY:
0.0000304
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:
0.0000547
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000337
AC:
49
AN:
1455988
Hom.:
0
Cov.:
28
AF XY:
0.0000290
AC XY:
21
AN XY:
724000
show subpopulations
African (AFR)
AF:
0.0000899
AC:
3
AN:
33372
American (AMR)
AF:
0.00
AC:
0
AN:
44380
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25994
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39454
South Asian (SAS)
AF:
0.0000586
AC:
5
AN:
85358
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53172
Middle Eastern (MID)
AF:
0.000697
AC:
4
AN:
5738
European-Non Finnish (NFE)
AF:
0.0000316
AC:
35
AN:
1108414
Other (OTH)
AF:
0.0000333
AC:
2
AN:
60106
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.431
Heterozygous variant carriers
0
3
6
9
12
15
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:
151992
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74218
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000242
AC:
1
AN:
41398
American (AMR)
AF:
0.00
AC:
0
AN:
15260
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
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:
67922
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.325
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:
0.0000151
ExAC
AF:
0.0000249
AC:
3

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Joubert syndrome Uncertain:1
Oct 05, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 767 of the AHI1 protein (p.Val767Leu). This variant is present in population databases (rs755688765, gnomAD 0.01%). This missense change has been observed in individual(s) with clinical features of Joubert syndrome (PMID: 30755392). ClinVar contains an entry for this variant (Variation ID: 260843). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt AHI1 protein function. 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. -

Joubert syndrome 3 Uncertain:1
Apr 09, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Nov 19, 2018
Center for Personalized Medicine, Children's Hospital Los Angeles
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Retinal dystrophy Uncertain:1
Jan 01, 2022
Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
-
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Benign
-0.30
T
BayesDel_noAF
Benign
-0.46
CADD
Benign
9.0
DANN
Benign
0.57
DEOGEN2
Benign
0.076
T;T;T;.
Eigen
Benign
-0.81
Eigen_PC
Benign
-0.69
FATHMM_MKL
Benign
0.099
N
LIST_S2
Uncertain
0.86
.;.;D;D
M_CAP
Benign
0.0064
T
MetaRNN
Benign
0.039
T;T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-0.41
N;N;N;N
PhyloP100
0.31
PrimateAI
Benign
0.37
T
PROVEAN
Benign
0.47
N;N;N;N
REVEL
Benign
0.060
Sift
Benign
0.72
T;T;T;T
Sift4G
Benign
1.0
T;T;T;T
Polyphen
0.13
B;B;B;B
Vest4
0.14
MutPred
0.57
Loss of helix (P = 0.3949);Loss of helix (P = 0.3949);Loss of helix (P = 0.3949);Loss of helix (P = 0.3949);
MVP
0.26
MPC
0.044
ClinPred
0.041
T
GERP RS
0.86
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.074
gMVP
0.26
Mutation Taster
=97/3
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs755688765; hg19: chr6-135752420; API