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Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease
Published on: April 4, 2018
Stickler-like syndrome due to a dominant negative mutation in the COL2A1 gene
R Ballo1, P H Beighton, R S Ramesar
1MRC Research Unit for Medical Genetics and Department of Human Genetics, University of Cape Town Medical School, South Africa.
Abstract:
The type II collagenopathies include a wide spectrum of phenotypes ranging from mild spondylo epiphyseal dysplasia (SED) to severe achondrogenesis/hypochondrogenesis. Several attempts have been made at providing phenotype-genotype correlations in this group of disorders. In this report we discuss a South African family in which four members have a phenotype resembling Stickler syndrome type 1. Ocular problems and conductive deafness predominate, while skeletal changes resemble those of a mild form of multiple epiphyseal dysplasia (MED). In distinction to the classical form of Stickler syndrome, the affected persons have stubby digits. DNA analysis of the exons of the COL2A1 gene documented a C-T transversion in exon 39, resulting in an Arg704Cys substitution in the triple helical domain of the type II collagen peptide; this nontermination mutation may be indicative of further heterogeneity in the Stickler group of disorders or of a new syndrome amongst the type II collagenopathies.
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