The Begain gene marks the centromeric boundary of the imprinted region on mouse chromosome 12

Although the central portion of the imprinted region on mouse chromosome 12 has been intensively analysed in the past, little is known about the neighbouring centromeric genes. A DNA sequence comparison shows that the region upstream of Dlk1 and Gtl2 is dominated by an expanded cluster of repetitive elements in the mouse. These elements separate the paternally expressed Dlk1 gene from the centromeric Begain gene. Despite the long physical distance to the IG-DMR imprinting centre, Begain is subjected to genomic imprinting. Similar to the ovine Begain gene, the homologous mouse gene encodes two different transcript variants, one of which shows a strong bias toward paternal transcription. Nevertheless, imprinting effects do not spread further centromeric to the Wdr25 gene, which is biallelically expressed as the previously studied neighbouring Wars and Yy1 genes.