18kb genomic fragment containing the lncRNA:let7C locus, which comprises the mir-100, mir-let7 and mir-125 microRNAs.
Adults transheterozygous for lncRNA:let7CKO2/Df(2L)let-7-CGKI and also bearing lncRNA:let7C+tCa and lncRNA:let7C3.3 exhibit a progressive brain vacuolization.