Fine mapping of the X-linked recessive congenital idiopathic nystagmus locus at Xq24-q26.3.

Purpose: To refine the interval for X-linked congenital idiopathic nystagmus at Xq24-q26.3 and to evaluate a novel candidate gene (Muscleblind-like 3 gene [MBNL3]).

Methods: A single pedigree with congenital idiopathic nystagmus (CIN) inherited as an X-linked recessive trait underwent detailed clinical examination including nystagmology and electrophysiological investigation in selected subjects.