A novel maternally expressed gene, ATP10C, encodes a putative aminophospholipid translocase associated with Angelman syndrome.

Lack of a maternal contribution to the genome at the imprinted domain on proximal chromosome 15 causes Angelman syndrome (AS) associated with neurobehavioral anomalies that include severe mental retardation, ataxia and epilepsy. Although AS patients have infrequent mutations in the gene encoding an E6-AP ubiquitin ligase required for long-term synaptic potentiation (LTP), most cases are attributed to de novo maternal deletions of 15q11-q13. We report here that a novel maternally expressed gene, ATP10C, maps within the most common interval of deletion and that ATP10C expression is virtually absent from AS patients with imprinting mutations, as well as from patients with maternal deletions of 15q11-q13.