rs771076928
Variant summary
Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong
The NM_000104.4(CYP1B1):c.535delG(p.Ala179ArgfsTer18) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000512 in 1,563,088 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.
Frequency
Consequence
NM_000104.4 frameshift
Scores
Clinical Significance
Conservation
Publications
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ACMG classification
Our verdict: Pathogenic. The variant received 16 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| CYP1B1 | NM_000104.4 | c.535delG | p.Ala179ArgfsTer18 | frameshift_variant | Exon 2 of 3 | ENST00000610745.5 | NP_000095.2 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000591 AC: 9AN: 152238Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.0000512 AC: 8AN: 156224 AF XY: 0.0000467 show subpopulations
GnomAD4 exome AF: 0.0000503 AC: 71AN: 1410732Hom.: 0 Cov.: 31 AF XY: 0.0000531 AC XY: 37AN XY: 697332 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000591 AC: 9AN: 152356Hom.: 0 Cov.: 33 AF XY: 0.0000671 AC XY: 5AN XY: 74508 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
Glaucoma 3A Pathogenic:4
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ACMG classification criteria: PVS1 very strong, PM2 supporting, PM3 strong -
The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: 0.005%). Predicted Consequence/Location: Frameshift: predicted to result in a loss or disruption of normal protein function through nonsense-mediated decay (NMD) or protein truncation. Multiple pathogenic variants are reported downstream of the variant. The variant has been reported at least twice as pathogenic with clinical assertions and evidence for the classification (ClinVar ID: VCV000523943 /PMID: 12372064). Therefore, this variant is classified as Pathogenic according to the recommendation of ACMG/AMP guideline. -
Anterior segment dysgenesis 6 Pathogenic:2
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not provided Pathogenic:2
The c.535delG variant in the CYP1B1 gene has been reported previously in association with autosomal recessive primary congenital glaucoma, and has been reported as a founder mutation in the Moroccan population (Belmouden et al., 2002; Gronskov et al., 2016). This variant causes a frameshift starting with codon Alanine 179, changes this amino acid to an Arginine residue, and creates a premature Stop codon at position 18 of the new reading frame, denoted p.Ala179ArgfsX18. This variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. The c.535delG variant is observed in 4/26120 (0.015%) alleles from individuals of Latino background and 7/182840 (0.004%) global alleles in large population cohorts, with no homozygotes identified (Lek et al., 2016). We interpret c.535delG as a pathogenic variant. -
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Glaucoma 3, primary infantile, B;C1856439:Glaucoma 3A;C4310623:Anterior segment dysgenesis 6 Pathogenic:1
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Primary congenital glaucoma Pathogenic:1
Variant summary: CYP1B1 c.535delG (p.Ala179ArgfsX18) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant allele was found at a frequency of 5.1e-05 in 156224 control chromosomes (gnomAD). c.535delG has been reported in the literature in at least an individual affected with Primary Congenital Glaucoma (example: Reis_2016). These data indicate that the variant may be associated with disease. The following publication has been ascertained in the context of this evaluation (PMID: 27272408). ClinVar contains an entry for this variant (Variation ID: 523943). Based on the evidence outlined above, the variant was classified as pathogenic. -
CYP1B1-related disorder Pathogenic:1
The CYP1B1 c.535delG variant is predicted to result in a frameshift and premature protein termination (p.Ala179Argfs*18). This variant was reported in the homozygous or compound heterozygous state to be causative for primary congenital glaucoma (described as 4339delG, Bouyacoub et al. 2014. PubMed ID: 24942078; Cardoso et al. 2015. PubMed ID: 25952714; García-Antón et al. 2017. PubMed ID: 28448622). This variant is reported in 0.019% of alleles in individuals of Latino descent in gnomAD (http://gnomad.broadinstitute.org/variant/2-38301996-GC-G). Frameshift variants in CYP1B1 are expected to be pathogenic. This variant is interpreted as pathogenic. -
Congenital glaucoma Pathogenic:1
This sequence change creates a premature translational stop signal (p.Ala179Argfs*18) in the CYP1B1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in CYP1B1 are known to be pathogenic (PMID: 9097971, 9497261, 19234632). This variant is present in population databases (rs771076928, gnomAD 0.02%). This premature translational stop signal has been observed in individuals with open-angle glaucoma, and primary congenital glaucoma (PMID: 12372064, 19234632, 23922489, 27272408, 27777502, 27820421). It has also been observed to segregate with disease in related individuals. This variant is also known as c.4339delG, c.906delG, c.534_535delG (p.Ala179ArgfsX16). ClinVar contains an entry for this variant (Variation ID: 523943). For these reasons, this variant has been classified as Pathogenic. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at