Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2
The NM_181503.3(EXOSC8):c.815G>T(p.Ser272Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S272T) has been classified as Uncertain significance.
EXOSC8 (HGNC:17035): (exosome component 8) This gene encodes a 3'-5' exoribonuclease that specifically interacts with mRNAs containing AU-rich elements. The encoded protein is part of the exosome complex that is important for the degradation of numerous RNA species. A pseudogene of this gene is found on chromosome 6. [provided by RefSeq, Mar 2009]
SUPT20H (HGNC:20596): (SPT20 homolog, SAGA complex component) Predicted to enable transcription coregulator activity. Predicted to be involved in regulation of transcription by RNA polymerase II. Predicted to act upstream of or within positive regulation of gluconeogenesis and positive regulation of transcription by RNA polymerase II. Part of SAGA-type complex. [provided by Alliance of Genome Resources, Apr 2022]
The c.815G>T (p.S272I) alteration is located in exon 11 (coding exon 11) of the EXOSC8 gene. This alteration results from a G to T substitution at nucleotide position 815, causing the serine (S) at amino acid position 272 to be replaced by an isoleucine (I). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -