Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4
The NM_018723.4(RBFOX1):c.931-5226T>A variant causes a intron change. The variant allele was found at a frequency of 0.000000688 in 1,453,488 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).
RBFOX1 (HGNC:18222): (RNA binding fox-1 homolog 1) The Fox-1 family of RNA-binding proteins is evolutionarily conserved, and regulates tissue-specific alternative splicing in metazoa. Fox-1 recognizes a (U)GCAUG stretch in regulated exons or in flanking introns. The protein binds to the C-terminus of ataxin-2 and may contribute to the restricted pathology of spinocerebellar ataxia type 2 (SCA2). Ataxin-2 is the product of the SCA2 gene which causes familial neurodegenerative diseases. Fox-1 and ataxin-2 are both localized in the trans-Golgi network. Several alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2011]
Review Status: criteria provided, single submitter
Collection Method: clinical testing
Algorithms developed to predict the effect of nucleotide changes on mRNA splicing suggest that this intronic variant may alter mRNA splicing, but this prediction has not been confirmed by published transcriptional studies. This sequence change falls in intron 9 of the RBFOX1 mRNA. It does not directly change the encoded amino acid sequence of the RBFOX1 protein. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a RBFOX1-related disease. In summary, this variant is a novel missense change with uncertain impact on mRNA splicing. It has been classified as a Variant of Uncertain Significance. -