Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PM5PP3_Moderate
The NM_003801.4(GPAA1):c.1165G>A(p.Ala389Thr) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.00000622 in 1,606,702 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 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. A389P) has been classified as Pathogenic.
GPAA1 (HGNC:4446): (glycosylphosphatidylinositol anchor attachment 1) Posttranslational glycosylphosphatidylinositol (GPI) anchor attachment serves as a general mechanism for linking proteins to the cell surface membrane. The protein encoded by this gene presumably functions in GPI anchoring at the GPI transfer step. The mRNA transcript is ubiquitously expressed in both fetal and adult tissues. The anchor attachment protein 1 contains an N-terminal signal sequence, 1 cAMP- and cGMP-dependent protein kinase phosphorylation site, 1 leucine zipper pattern, 2 potential N-glycosylation sites, and 8 putative transmembrane domains. [provided by RefSeq, Jul 2008]