PURPOSE: To confirm and define a molecular basis for a case of mucolipidosis type IV (ML IV) with an extremely atypical phenotype pattern. DESIGN: Observational case report of a patient with ML IV with disease progression restricted to ocular symptoms. METHODS: Complete ophthalmologic and neurologic examination. Ultrastructural examination of white blood cells, skin, conjunctiva, and corneal epithelium. The MCOLN1 gene was sequenced from cDNA and the proportion of splicing variants were assessed by quantitative allele-specific polymerase chain reaction. RESULTS: Absence of any neurological abnormalities. Retinal pathologic features were the main cause of visual disability: low visual acuity and cloudy corneas since 2 years of age, progressive decrease in visual acuity since the age of 9 years. Ultrastructural examination showed storage lysosomes filled with either concentric membranes or lucent precipitate in corneal and conjunctive epithelia and in vascular endothelium. Cultured fibroblasts were free of any autofluorescence. Sequencing of the MCOLN1 gene identified compound heterozygosity for D362Y and A-->T transition leading to the creation of a novel donor splicing site and a 4-bp deletion from exon 13 at the mRNA level. Both normal and pathologic splice forms were detected in skin fibroblasts and leukocytes, with the normal form being more abundant. CONCLUSIONS: The case of this patient with ML IV is unique and is characterized by a curious lack of generalized symptoms. In this patient, the disorder was limited to the eyes and appeared without the usual psychomotor deterioration. The resulting phenotype is the mildest seen to date.

• MeSH
• alternativní sestřih genetika   MeSH
• degenerace retiny genetika   patologie   MeSH
• dítě MeSH
• elektroretinografie MeSH
• epitelové buňky ultrastruktura   MeSH
• fenotyp MeSH
• fibroblasty ultrastruktura   MeSH
• kationtové kanály TRP MeSH
• kationtové kanály TRPM genetika   MeSH
• kůže ultrastruktura   MeSH
• leukocyty ultrastruktura   MeSH
• lidé MeSH
• lyzozomy genetika   ultrastruktura   MeSH
• messenger RNA genetika   MeSH
• mukolipidózy genetika   patologie   MeSH
• mutace * MeSH
• mutační analýza DNA MeSH
• nemoci rohovky genetika   patologie   MeSH
• nemoci spojivky genetika   patologie   MeSH
• polymerázová řetězová reakce MeSH
• rohovkový epitel ultrastruktura   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kationtové kanály TRP MeSH
• kationtové kanály TRPM MeSH
• MCOLN1 protein, human MeSH Prohlížeč
• messenger RNA MeSH