Testing the Weak Form of Efficient Market Hypothesis in Nigerian Capital Market

Abstract

Isolated congenital anosmia (ICA) is a rare disorder, where otherwise healthy individuals present with an inability to smell since birth. A list of studies have described the genes involved in syndromic anosmia; however the genetics of ICA is still in its infancy. So far no mutations have been identified in human ICA outside the list. Studies in mice show that the cyclic nucleotide gated channel subunit CNGA2, expressed in the olfactory epithelium has a crucial role in olfactory signal transduction. We have identified a novel X-linked stop mutation in CNGA2 (c.634C>T, p.R212*) in two brothers with ICA using exome sequencing. No additional mutations in CNGA2 were identified in a cohort of 31 non-related ICA individuals. Magnetic resonance brain imaging revealed diminished olfactory bulbs and flattened olfactory sulci. This is the first report of a mutation in the cyclic nucleotide gated gene CNGA2 and supports the critical role of this gene in human olfaction. possibly the first mutation reported in humans with isolated congenital anosmia.