What is the biochemical defect in the Zellweger syndrome?: (A) Peroxisomal biogenesis disorder, (B) Lysosomal targeting disorder, (C) Defect in glycosylation of proteins, (D) Trisomy 21
Answer is A. Ans. A. Peroxisomal biogenesis disorderBiochemical defect in Zellweger SyndromeThere is gene defects, involving mainly the import of proteins that contain the PTS1 targeting signal* Zellweger syndrome (most severe)Clinical picture* Typical facial appearance (high forehead, unslanting palpebral fissures, hypoplastic supraorbital ridges, and epicanthal folds)* Severe weakness and hypotonia, neonatal seizures* Eye abnormalities (cataracts, glaucoma, corneal clouding, Brushfield spots, pigmentary retinopathy, and nerve dysplasia)* Because of the hypotonia and "mongoloid" appearance, Down syndrome may be suspected