Our verdict is Benign. Variant got -7 ACMG points: 2P and 9B. PM2BP4_StrongBP6BS1
The NM_001134831.2(AHI1):āc.2831A>Gā(p.Gln944Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000657 in 1,613,238 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
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]
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.026212275).
BP6
Variant 6-135411478-T-C is Benign according to our data. Variant chr6-135411478-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 376893.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=2}.
BS1
Variant frequency is greater than expected in population afr. gnomad4_exome allele frequency = 0.0000424 (62/1460962) while in subpopulation AFR AF= 0.00152 (51/33458). AF 95% confidence interval is 0.00119. There are 1 homozygotes in gnomad4_exome. There are 23 alleles in male gnomad4_exome subpopulation. Median coverage is 30. This position pass quality control queck.
Review Status: criteria provided, single submitter
Collection Method: clinical testing
The c.2831A>G (p.Q944R) alteration is located in exon 20 (coding exon 18) of the AHI1 gene. This alteration results from a A to G substitution at nucleotide position 2831, causing the glutamine (Q) at amino acid position 944 to be replaced by an arginine (R). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -
Optic atrophy Uncertain:1
Jan 01, 2023
Institute of Human Genetics, Univ. Regensburg, Univ. Regensburg
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing
- -
not provided Uncertain:1
Jun 14, 2016
Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing
- -
Familial aplasia of the vermis Benign:1
Feb 01, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely benign
Review Status: criteria provided, single submitter