Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1PM2
The NM_001368894.2(PAX6):c.1075-2A>C variant causes a splice acceptor, intron change. The variant was absent in control chromosomes in GnomAD project. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.
PAX6 (HGNC:8620): (paired box 6) This gene encodes paired box protein Pax-6, one of many human homologs of the Drosophila melanogaster gene prd. In addition to a conserved paired box domain, a hallmark feature of this gene family, the encoded protein also contains a homeobox domain. Both domains are known to bind DNA and function as regulators of gene transcription. Activity of this protein is key in the development of neural tissues, particularly the eye. This gene is regulated by multiple enhancers located up to hundreds of kilobases distant from this locus. Mutations in this gene or in the enhancer regions can cause ocular disorders such as aniridia and Peter's anomaly. Use of alternate promoters and alternative splicing results in multiple transcript variants encoding different isoforms. Interestingly, inclusion of a particular alternate coding exon has been shown to increase the length of the paired box domain and alter its DNA binding specificity. Consequently, isoforms that carry the shorter paired box domain regulate a different set of genes compared to the isoforms carrying the longer paired box domain. [provided by RefSeq, Mar 2019]
PAX6 Gene-Disease associations (from GenCC):
aniridia 1
Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
PAX6-related ocular dysgenesis
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
Our verdict: Pathogenic. The variant received 10 ACMG points.
PVS1
Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 8.2, offset of 7, new splice context is: tctctcctcaccgcccccAGtcc. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
PM2
Very rare variant in population databases, with high coverage;
Variant Effect in Transcripts
ACMG analysis was done for transcript: NM_001368894.2. You can select a different transcript below to see updated ACMG assignments.