NM_001134831.2:c.1997A>T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM1PP3_ModeratePP5_Very_Strong

The NM_001134831.2(AHI1):​c.1997A>T​(p.Asp666Val) variant causes a missense change. The variant allele was found at a frequency of 0.00000508 in 1,574,294 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

AHI1
NM_001134831.2 missense

Scores

3
12
4

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 5.41

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: Pathogenic. The variant received 12 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_001134831.2
PP3
MetaRNN computational evidence supports a deleterious effect, 0.887
PP5
Variant 6-135438414-T-A is Pathogenic according to our data. Variant chr6-135438414-T-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 217548.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
AHI1NM_001134831.2 linkc.1997A>T p.Asp666Val missense_variant Exon 15 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.1997A>T p.Asp666Val missense_variant Exon 15 of 29 1 NM_001134831.2 ENSP00000265602.6 Q8N157-1

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152152
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000104
AC:
2
AN:
192618
AF XY:
0.0000196
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:
0.0000247
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000211
AC:
3
AN:
1422142
Hom.:
0
Cov.:
30
AF XY:
0.00000427
AC XY:
3
AN XY:
703358
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32776
American (AMR)
AF:
0.00
AC:
0
AN:
39706
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25362
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38258
South Asian (SAS)
AF:
0.00
AC:
0
AN:
80472
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51096
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5706
European-Non Finnish (NFE)
AF:
0.00000275
AC:
3
AN:
1089904
Other (OTH)
AF:
0.00
AC:
0
AN:
58862
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.408
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000329
AC:
5
AN:
152152
Hom.:
0
Cov.:
33
AF XY:
0.0000404
AC XY:
3
AN XY:
74330
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41442
American (AMR)
AF:
0.00
AC:
0
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68000
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
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

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:
0.0000450
Hom.:
0
Bravo
AF:
0.0000227

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Joubert syndrome 3 Pathogenic:1
Feb 23, 2015
UW Hindbrain Malformation Research Program, University of Washington
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

Joubert syndrome Pathogenic:1
Jun 30, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with valine, which is neutral and non-polar, at codon 666 of the AHI1 protein (p.Asp666Val). This variant is present in population databases (no rsID available, gnomAD 0.003%). This missense change has been observed in individual(s) with clinical features of Joubert syndrome (PMID: 26092869; Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 217548). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on AHI1 protein function. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1
Dec 03, 2015
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

p.Asp666Val (D666V) (GAT>GTT): c.1997 A>T in exon 14 of the AHI1 gene (NM_017651.4) The D666V variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. It was not observed in approximately 6,000 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these population. The D666V variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved in mammals, and in silico analysis predicts this variant is probably damaging to the protein structure/function. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Uncertain
0.097
D
BayesDel_noAF
Uncertain
-0.050
CADD
Pathogenic
28
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.42
T;T;T;.
Eigen
Uncertain
0.39
Eigen_PC
Uncertain
0.48
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.94
.;.;D;D
M_CAP
Benign
0.074
D
MetaRNN
Pathogenic
0.89
D;D;D;D
MetaSVM
Benign
-0.83
T
MutationAssessor
Uncertain
2.0
M;M;M;M
PhyloP100
5.4
PrimateAI
Benign
0.37
T
PROVEAN
Pathogenic
-6.2
D;D;D;D
REVEL
Uncertain
0.51
Sift
Uncertain
0.0010
D;D;D;D
Sift4G
Uncertain
0.0020
D;D;D;D
Polyphen
1.0
D;D;D;D
Vest4
0.88
MutPred
0.69
Loss of disorder (P = 0.0098);Loss of disorder (P = 0.0098);Loss of disorder (P = 0.0098);Loss of disorder (P = 0.0098);
MVP
0.73
MPC
0.34
ClinPred
0.98
D
GERP RS
5.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.68
gMVP
0.83
Mutation Taster
=2/98
disease causing (ClinVar)

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: rs863225147; hg19: chr6-135759552; API