PUBLICATION
Heterozygous pathogenic STT3A variation leads to dominant congenital glycosylation disorders and functional validation in zebrafish
- Authors
- Meng, L., Fang, Z., Jiang, L., Zheng, Y., Hong, S., Deng, Y., Xie, L.
- ID
- ZDB-PUB-250202-8
- Date
- 2025
- Source
- Orphanet journal of rare diseases 20: 4646 (Journal)
- Registered Authors
- Keywords
- STT3A gene, Congenital glycosylation disorders, Dominant inheritance, Phenotype, Zebrafish
- MeSH Terms
-
- Female
- Humans
- Hexosyltransferases/genetics
- Hexosyltransferases/metabolism
- Zebrafish*/genetics
- Animals
- Membrane Proteins*/genetics
- Membrane Proteins*/metabolism
- Heterozygote
- HEK293 Cells
- Male
- Glycosylation
- Congenital Disorders of Glycosylation*/genetics
- Congenital Disorders of Glycosylation*/metabolism
- Congenital Disorders of Glycosylation*/pathology
- PubMed
- 39891251 Full text @ Orphanet J Rare Dis
Citation
Meng, L., Fang, Z., Jiang, L., Zheng, Y., Hong, S., Deng, Y., Xie, L. (2025) Heterozygous pathogenic STT3A variation leads to dominant congenital glycosylation disorders and functional validation in zebrafish. Orphanet journal of rare diseases. 20:4646.
Abstract
Background Congenital disorders of glycosylation are a rare group of disorders characterized by impaired glycosylation, wherein STT3A encodes the catalytic subunit of the oligosaccharyltransferase complex, which is crucial for protein N-glycosylation. Previous studies have reported that STT3A-CDG is caused by autosomal recessive inheritance. However, in this study, we propose that STT3A-CDG can be pathogenic through autosomal dominant inheritance.
Methods The variant was identified via trio whole-exome sequencing. We constructed wild-type and variant plasmids, transfected them into HEK293T cells and detected the expression levels of the STT3A protein. We performed CRISPR-Cas9 to establish heterozygous knockdown zebrafish to validate the functional implications of autosomal dominant inheritance of STT3A in pathogenesis.
Results The patient presented with developmental delay, distinctive facial features, short stature, and abnormal discharges. The heterozygous pathogenic missense variant (NM_001278503.2: c.499G > T, NP_001265432.1:p. Asp167Tyr) was identified, and the Western blot results revealed a significant decrease in protein levels. Heterozygous knockdown zebrafish exhibit phenotypes similar to those of patients, including craniofacial dysmorphology (increased eye distance, increased Basihyal's length, increased Ceratohyal's angle), skeletal abnormalities (reduced number of mineralized bones), developmental delay (reduced adaptability under light‒dark stimuli suggesting abnormal locomotion, orientation, and social behavior), and electrophysiological abnormalities.
Conclusion We report a proband with a dominant congenital glycosylation disorder caused by heterozygous pathogenic STT3A variation, which is a new inheritance pattern of STT3A. Our report expands the known phenotype of dominant STT3A-CDGs. Furthermore, we provide in vivo validation through the establishment of a heterozygous knockdown zebrafish model for stt3a and strengthened the compelling evidence for dominant STT3A-related pathogenesis.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping