Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1PM2PP3PP5
The NM_001042432.2(CLN3):c.49G>T(p.Glu17Ter) variant causes a stop gained, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,740 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (no stars).
CLN3 (HGNC:2074): (CLN3 lysosomal/endosomal transmembrane protein, battenin) This gene encodes a protein that is involved in lysosomal function. Mutations in this, as well as other neuronal ceroid-lipofuscinosis (CLN) genes, cause neurodegenerative diseases commonly known as Batten disease or collectively known as neuronal ceroid lipofuscinoses (NCLs). Many alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Jul 2008]
Verdict is Pathogenic. Variant got 12 ACMG points.
PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 134 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 16-28491558-C-A is Pathogenic according to our data. Variant chr16-28491558-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 56276.Status of the report is no_assertion_criteria_provided, 0 stars. Variant chr16-28491558-C-A is described in Lovd as [Pathogenic].