Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2PP3
The NM_001042432.2(CLN3):c.1195G>A(p.Glu399Lys) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E399D) has been classified as Uncertain significance.
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]
CLN3 Gene-Disease associations (from GenCC):
inherited retinal dystrophy
Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
neuronal ceroid lipofuscinosis
Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
neuronal ceroid lipofuscinosis 3
Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae), Myriad Women’s Health
Gain of ubiquitination at E399 (P = 0.0131);Gain of ubiquitination at E399 (P = 0.0131);.;.;.;.;.;Gain of ubiquitination at E399 (P = 0.0131);.;.;.;.;.;