rs777420094

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001134831.2(AHI1):​c.983G>T​(p.Ser328Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000539 in 1,613,868 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 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 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000057 ( 0 hom. )

Consequence

AHI1
NM_001134831.2 missense

Scores

5
11

Clinical Significance

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

Conservation

PhyloP100: 1.24

Publications

0 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.

BP4
Computational evidence support a benign effect (MetaRNN=0.14555922).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
AHI1NM_001134831.2 linkc.983G>T p.Ser328Ile missense_variant Exon 9 of 29 ENST00000265602.11 NP_001128303.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
AHI1ENST00000265602.11 linkc.983G>T p.Ser328Ile missense_variant Exon 9 of 29 1 NM_001134831.2 ENSP00000265602.6

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152108
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:
0.00
Gnomad SAS
AF:
0.000829
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000108
AC:
27
AN:
249200
AF XY:
0.000133
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000568
AC:
83
AN:
1461642
Hom.:
0
Cov.:
31
AF XY:
0.0000784
AC XY:
57
AN XY:
727102
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39672
South Asian (SAS)
AF:
0.000927
AC:
80
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53400
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1111842
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60372
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.459
Heterozygous variant carriers
0
6
11
17
22
28
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:
0.0000263
AC:
4
AN:
152226
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74438
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41530
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.000829
AC:
4
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10608
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67998
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.588
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

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:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.0000993
AC:
12

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Oct 04, 2016
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Inborn genetic diseases Uncertain:1
Jul 03, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.983G>T (p.S328I) alteration is located in exon 8 (coding exon 6) of the AHI1 gene. This alteration results from a G to T substitution at nucleotide position 983, causing the serine (S) at amino acid position 328 to be replaced by an isoleucine (I). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear.

Joubert syndrome 3 Uncertain:1
Apr 20, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

not provided Uncertain:1
Oct 31, 2017
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The S328I variant in the AHI1 gene has not been reported previously as a pathogenic variant, nor as a benign variant, to our knowledge. The S328I variant is observed in 26/30780 (0.084%) alleles from individuals of South Asian background, in large population cohorts (Lek et al., 2016). The S328I 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 not conserved. In silico analysis is inconsistent in its predictions as to whether or not the variant is damaging to the protein structure/function. We interpret S328I as a variant of uncertain significance.

Joubert syndrome Benign:1
May 09, 2024
Labcorp Genetics (formerly Invitae), Labcorp
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
0.16
BayesDel_addAF
Benign
-0.29
T
BayesDel_noAF
Benign
-0.27
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Benign
0.23
T;T;T;.
Eigen
Uncertain
0.31
Eigen_PC
Uncertain
0.32
LIST_S2
Benign
0.0
.;.;T;T
M_CAP
Benign
0.050
D
MetaRNN
Benign
0.15
T;T;T;T
MetaSVM
Benign
-0.80
T
MutationAssessor
Uncertain
2.2
M;M;M;M
PhyloP100
1.2
PrimateAI
Benign
0.36
T
PROVEAN
Benign
-1.8
N;N;N;N
Sift
Uncertain
0.0080
D;D;D;D
Sift4G
Benign
0.12
T;T;T;T
Vest4
0.33
ClinPred
0.20
T
GERP RS
5.5
PromoterAI
-0.0028
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.15
gMVP
0.22
Mutation Taster
=94/6
polymorphism

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: rs777420094; hg19: chr6-135778800; API