Qkv mouse line is a well-known spontaneous mutant mouse line, in which a 1 Mb promoter/enhancer region is deleted at the upstream of the Qki transcription start site and results in myelination defect in the central nervous system (Sidman et al., 1964; Chenard and Richard, 2008), thus confirming the relevance of its role in causing human neurological diseases. The gene discussed is QKI; the disease is nervous system disorder.