Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2BP4_StrongBS1_Supporting
The NM_025265.4(TSEN2):c.-201C>T variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000217 in 152,236 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 (★).
TSEN2 (HGNC:28422): (tRNA splicing endonuclease subunit 2) This gene encodes one of the subunits of the tRNA splicing endonuclease. This endonuclease catalyzes the first step in RNA splicing which is the removal of introns. Mutations in this gene have been associated with pontocerebellar hypoplasia type 2. A pseudogene has been identified on chromosome 4. Multiple transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Feb 2009]
Verdict is Likely_benign. Variant got -3 ACMG points.
PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.79).
BS1
Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.000217 (33/152236) while in subpopulation NFE AF= 0.000353 (24/68042). AF 95% confidence interval is 0.000243. There are 0 homozygotes in gnomad4. There are 20 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -