To understand the molecular etiology of isolated MD (MD without EVA) and provide possible genetic testing and counseling for hearing loss patients with isolated MD in China, we performed SLC26A4 sequence analysis in 28 patients with isolated MD, 50 patients with EVA and MD, 50 patients with isolated EVA, and 16 patients with other forms of IEM. This evidence concerns the gene SLC26A4 and Menkes disease.