Wld^s

The underlying mutation is an 85-kb tandem triplication on chromosome 4. This triplication results in the expression of an abnormal transcript that encodes a fusion of the N-terminal fragment of ubiquitination factor E4B (Ube4b) fused to nicotinamide mononucleotide adenylyltransferase 1 (Nmnat1). (J:49401, J:65178, J:72936, J:75678)