Abstract
Mucolipidosis Type IV (MLIV) is caused by a deficiency of the mucolipin cation channel encoded by Mucolipin TRP Cation Channel 1 gene (MCOLN1). It is a slowly progressive neurodevelopmental and neurodegenerative disorder causing severe psychomotor developmental delay and progressive visual impairment, which is often misdiagnosed as cerebral palsy. We describe six patients with MLIV from two Omani families with a novel c.237+5G>A mutation in the MCOLN1 gene predicted to affect mRNA splicing. Mutation screening with a high-resolution melting (HRM) assay in a large population sample did not detect this mutation in control subjects. This report highlights the importance of considering MLIV in the differential diagnosis of patients in a pediatric age group with cerebral palsy-like presentation. Although the same rare mutation was seen in two apparently unrelated families, this was not seen in the sample screened from the general population. The HRM assay provides a cost-effective assay for population screening for the c.237+5G>A mutation.
Highlights
Defects in lysosomal degradation pathways result in a group of inherited disorders known as lysosomal storage disorders (LSDs)
Diagnosis is confirmed by documenting the presence of high gastrin level, the presence of thin corpus callosum in magnetic resonance imaging (MRI), accumulated amphiphilic lipids and water-soluble substances in skin biopsy and mutations in the Mucolipin TRP Cation Channel 1 gene (MCOLN1) gene [2]
Achlorhydria leads to iron deficiency anemia, a feature that is observed in some patients with Mucolipidosis Type IV (MLIV)
Summary
Defects in lysosomal degradation pathways result in a group of inherited disorders known as lysosomal storage disorders (LSDs). A deficiency of some lysosomal hydrolases sometimes causes the accumulation of undigested accumulating complex lamellar and granular material composed of mucopolysaccharides and lipids. These complexes are detected in histopathological staining and electron microscopy as membranous cytoplasmic inclusions and zebra bodies [1]. Mucolipidosis is categorized into four types: type I, type II, type III and type IV. Type IV mucolipidosis (MLIV) is a rare progressive neurodegenerative disorder causing severe psychomotor developmental delay, vision impairment due to progressive retinal degeneration and corneal clouding and achlorhydria. Achlorhydria leads to iron deficiency anemia, a feature that is observed in some patients with MLIV
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
