Genomic cloning and localization to chromosome 11p15.5 of the human achaete-scute homolog 2 (ASCL2)

The mouse achaete-scute homolog-2 gene (Mash2), a member of the achaete-scute gene family, encodes a transcription factor that plays an important role in the develop ment of the trophoblast. It has recently been reported that Mash2 is genomically imprinted and mapped to the distal region of mouse chromosome 7, where other imprinted genes, Ins2, Igf2 and H19 are located. We isolated a clone carrying the partial human homolog, ASCL2, from a human genomic phage library using a PCR product for the rat Ascl2-cDNA as a probe. By fluorescence in situ hybridization using a phage clone as a probe whose insert contained the partial human ASCL2, we assigned ASCL2 to human chromosome 11p15.5. Sequence comparisons of the human ASCL2 clone and the rat Ascl2-cDNA showed 86.9% identity spanning 206 nucleotides and 85.3% deduced polypeptide-sequence identity over 68 residues.