Haplo-lethal except in presence of duplication of functional copy of dpp-Hin region.
Deficiency lacks several vital loci distal to dpp.
Three copies of dpp::Hsap\BMP4fl.cPa or two copies of dppP23 completely rescues the embryonic dorsal-ventral patterning defect of null dppH61/Df(2L)DTD48 genotype.