rs878852979

Variant names:

• chr11-31810826-A-T
• rs878852979
• NM_001368894.2:c.-129+2T>A

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_001368894.2(PAX6):​c.-129+2T>A variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: PAX6 NM_001368894.2 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:3
• Conservation: PhyloP100: 8.40

Genes affected

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]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-31810826-A-T is Pathogenic according to our data. Variant chr11-31810826-A-T is described in ClinVar as [Pathogenic]. Clinvar id is 3482.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PAX6	NM_001368894.2	c.-129+2T>A		splice_donor_variant, intron_variant	Intron 2 of 13	ENST00000640368.2	NP_001355823.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PAX6	ENST00000640368.2	c.-129+2T>A		splice_donor_variant, intron_variant	Intron 2 of 13	5	NM_001368894.2	ENSP00000492024.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 0

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, single submitter

Submissions by phenotype

Aniridia 1 Pathogenic:2

Aug 15, 2019

Wessex Regional Genetics Laboratory, Salisbury District Hospital

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Dec 01, 2006

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Aniridia 1;C0344559:Irido-corneo-trabecular dysgenesis Pathogenic:1

Jul 20, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 3482). This variant is also known as IVS2+2T>A. This variant has been observed in individual(s) with aniridia (PMID: 32214788, 32360764). In at least one individual the variant was observed to be de novo. This variant is not present in population databases (gnomAD no frequency). This variant occurs in a non-coding region of the PAX6 gene. It does not change the encoded amino acid sequence of the PAX6 protein. It affects a nucleotide within the consensus splice site. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Uncertain	-0.040
CADD	Pathogenic	32
DANN	Uncertain	0.98
FATHMM_MKL	Pathogenic	0.98	D
GERP RS		4.4

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.92
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

LitVar

Other links and lift over

dbSNP: rs878852979; hg19: chr11-31832374;