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Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease
Published on: April 4, 2018
A novel mutation in the RSPO4 gene in a patient with autosomal recessive anonychia
S Khalil1, R Hayashi2, L Daou3
1Department of Internal Medicine, American University of Beirut, Beirut, Lebanon.
Abstract:
The Wnt signalling pathway is a major pathway involved in the embryogenic development of the various organs of the body. Appropriate signalling in this pathway relies on the proper functioning of several proteins including the R-spondin family of proteins. Deactivating mutations in R-spondin 4 are associated with anonychia. We present the case of a 26-year-old man presenting with anonychia of the 20 nails, which had been present since birth. Using genetic studies, we identified a novel nonsense mutation, c.164-165TC>AA, characterized by two consecutive mismatch bases. To our knowledge, this mutation is the first to be reported in R-spondin 4 in a Lebanese population. Evaluating new patients with anonychia provides fruitful clinical and molecular findings.
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