rs121434350

Variant names:

• chr6-135455750-A-T
• rs121434350
• NM_001134831.2:c.1328T>A

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM2 PP3_Strong PP5_Very_Strong

The NM_001134831.2(AHI1):​c.1328T>A​(p.Val443Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000208 in 1,442,842 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 (★★). Synonymous variant affecting the same amino acid position (i.e. V443V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: AHI1 NM_001134831.2 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 8.88
• Publications: 16 publications found

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, Laboratory for Molecular Medicine, ClinGen, Ambry Genetics
• retinitis pigmentosa

  Inheritance: AD, AR Classification: SUPPORTIVE, LIMITED Submitted by: Orphanet, Ambry Genetics
• Joubert syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Joubert syndrome with ocular defect

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.982
• PP5: Variant 6-135455750-A-T is Pathogenic according to our data. Variant chr6-135455750-A-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 2012.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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	AHI1	NM_001134831.2	MANE Select	c.1328T>A	p.Val443Asp	missense	Exon 10 of 29	NP_001128303.1	Q8N157-1
	AHI1	NM_001134830.2		c.1328T>A	p.Val443Asp	missense	Exon 8 of 27	NP_001128302.1	Q8N157-1
	AHI1	NM_001350503.2		c.1328T>A	p.Val443Asp	missense	Exon 10 of 29	NP_001337432.1	Q8N157-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	AHI1	ENST00000265602.11	TSL:1 MANE Select	c.1328T>A	p.Val443Asp	missense	Exon 10 of 29	ENSP00000265602.6	Q8N157-1
	AHI1	ENST00000367800.8	TSL:1	c.1328T>A	p.Val443Asp	missense	Exon 8 of 27	ENSP00000356774.4	Q8N157-1
	AHI1	ENST00000457866.6	TSL:1	c.1328T>A	p.Val443Asp	missense	Exon 9 of 28	ENSP00000388650.2	Q8N157-1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000208 AC: 3 AN: 1442842 Hom.: 0 Cov.: 30 AF XY: 0.00000140 AC XY: 1 AN XY: 716272

African (AFR) AF: 0.00 AC: 0 AN: 33156

American (AMR) AF: 0.00 AC: 0 AN: 43476

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25622

East Asian (EAS) AF: 0.00 AC: 0 AN: 39384

South Asian (SAS) AF: 0.00 AC: 0 AN: 82528

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52690

Middle Eastern (MID) AF: 0.000175 AC: 1 AN: 5708

European-Non Finnish (NFE) AF: 0.00000182 AC: 2 AN: 1100650

Other (OTH) AF: 0.00 AC: 0 AN: 59628

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	Joubert syndrome 3 (3)
1	-	-	Global developmental delay;CN228298:Typical Joubert syndrome MRI findings (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.28
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.69	D
Eigen	Pathogenic	0.80
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.41	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Uncertain	-0.18	T
MutationAssessor	Uncertain	2.8	M
PhyloP100		8.9
PrimateAI	Uncertain	0.65	T
PROVEAN	Pathogenic	-5.7	D
REVEL	Pathogenic	0.84
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.99
MutPred		0.87		Loss of sheet (P = 0.007)
MVP		0.85
MPC		0.30
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.90
gMVP		0.77
Mutation Taster		=1/99	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

Other links and lift over

dbSNP: rs121434350; hg19: chr6-135776888;