RNA-FISH showing biallelic expression of deregulated genes in the Snrpn cluster. Snrpn (green) and Ndn (red) RNA-FISH signals on ( A ) Smchd1+/+ and ( B ) Smchd1MommeD1/MommeD1 MEFs. Snrpn (green) and Magel2 (red) RNA-FISH signals on ( C ) Smchd1+/+ and ( D ) Smchd1MommeD1/MommeD1 MEFs. Images representative of the predominant hybridizing pattern for each genotype and gene combination are shown. The number of RNA-FISH signals per nucleus for ( E ) Snrpn/Ndn and ( F ) Snrpn/Magel2 were counted (100 randomly selected nuclei counted in each case) and plotted for each line of MEFs (Smchd1+/+, Smchd1MommeD1/MommeD1#1, and Smchd1MommeD1/MommeD1#2). The genotypes are indicated in each case.