Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_ModeratePM2
The NM_006279.5(ST3GAL3):c.3G>A(p.Met1?) variant causes a start lost change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).
ST3GAL3 (HGNC:10866): (ST3 beta-galactoside alpha-2,3-sialyltransferase 3) The protein encoded by this gene is a type II membrane protein that catalyzes the transfer of sialic acid from CMP-sialic acid to galactose-containing substrates. The encoded protein is normally found in the Golgi apparatus but can be proteolytically processed to a soluble form. This protein is a member of glycosyltransferase family 29. Mutations in this gene have been associated with a form of autosomal recessive nonsymdromic cognitive disability as well as infantile epileptic encephalopathy. Multiple transcript variants encoding several different isoforms have been found for this gene. [provided by RefSeq, Jul 2017]
Verdict is Uncertain_significance. Variant got 4 ACMG points.
PVS1
Start lost variant, next in-frame start position is after 2 pathogenic variants. Next in-frame start position is after 95 codons. Genomic position: 43838292. Lost 0.251 part of the original CDS.
PM2
Very rare variant in population databases, with high coverage;
Early infantile epileptic encephalopathy with suppression bursts Uncertain:1
Jun 03, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing
In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. ClinVar contains an entry for this variant (Variation ID: 1402972). This variant has not been reported in the literature in individuals affected with ST3GAL3-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change affects the initiator methionine of the ST3GAL3 mRNA. The next in-frame methionine is located at codon 95. -
Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);Gain of catalytic residue at M1 (P = 0.0062);