Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_StrongBS2
The NM_004993.6(ATXN3):c.947G>A(p.Cys316Tyr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000728 in 1,236,132 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).
ATXN3 (HGNC:7106): (ataxin 3) Machado-Joseph disease, also known as spinocerebellar ataxia-3, is an autosomal dominant neurologic disorder. The protein encoded by this gene contains (CAG)n repeats in the coding region, and the expansion of these repeats from the normal 12-44 to 52-86 is one cause of Machado-Joseph disease. There is a negative correlation between the age of onset and CAG repeat numbers. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Jul 2016]
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Dec 10, 2024
The c.947G>A (p.C316Y) alteration is located in exon 10 (coding exon 10) of the ATXN3 gene. This alteration results from a G to A substitution at nucleotide position 947, causing the cysteine (C) at amino acid position 316 to be replaced by a tyrosine (Y). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -
Gain of catalytic residue at C316 (P = 0.0085);.;.;.;Gain of catalytic residue at C316 (P = 0.0085);.;.;.;Gain of catalytic residue at C316 (P = 0.0085);.;.;.;.;.;