Background: The rapid spread of genome-wide next-generation sequencing in the molecular diagnosis of rare genetic disorders has produced increasing evidence of multilocus genomic variations in cases with a previously well-characterized molecular diagnosis. Here, we describe two patients with a rare combination of skeletal abnormalities and retinal dystrophy caused by variants in the SLC26A2 and ABCA4 genes, respectively, in a family with parental consanguinity.
Methods: Next-generation sequencing and Sanger sequencing were performed to obtain a molecular diagnosis for the retinal and skeletal phenotypes, respectively.
Rare genetic diseases and syndromes may appear with unique features in some patients. In genetically-solved cases, this situation indicates a phenotypic expansion of the syndrome with additional features (i.e.
View Article and Find Full Text PDFWe performed a complex analysis of the neurofibromatosis type 1 (NF1) gene in Slovakia based on direct cDNA sequencing supplemented by multiple ligation dependent probe amplification (MLPA) analysis. All 108 patients had café-au-lait spots, 85% had axilary and/or inguinal freckling, 61% neurofibromas, 36% Lisch nodules of the iris and 31% optic pathway glioma, 5% suffered from typical skeletal disorders, and 51% of patients had family members with NF1. In 78 of the 86 (90.
View Article and Find Full Text PDFThe Smith-Lemli-Opitz syndrome (SLOS), an autosomal recessive disorder associated with multiple developmental malformations, is caused by a large spectrum of mutations in the DHCR7 gene. Mutations in the DHCR7 gene lead to a 7-dehydrocholesterol reductase deficiency, which is the final enzyme in the pathway of the cholesterol biosynthesis. Reduced cholesterol levels and elevated concentrations of its precursor 7-dehydrocholesterol in plasma and tissues are the major biochemical hallmarks of this disorder.
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