Enhanced multiplex fish

A combination of nucleic acid molecules capable of hybridizing with a target nucleic acid sequence, wherein the combination comprises

• (a) at least one first nucleic acid molecule comprising
• (i) a sequence capable of hybridizing with the target sequence,
• (ii) two complementary sequences capable of forming a stem, and
• (iii) a luminescent group and a quencher group, wherein the quencher group quenches the fluorescent group if the nucleic acid forms a stem-loop structure, and wherein the fluorescent group is capable of emitting a luminescence signal upon excitation if the oligonucleotide is hybridized with the target sequence,
• (b) a second nucleic acid molecule, a third nucleic acid molecule, and optionally at least one further nucleic acid molecule, wherein the second nucleic acid molecule, the third nucleic acid molecule, and the optional at least one further nucleic acid molecule hybridize with the target sequence at a sequence located 5′ or/and 3′ from the sequence to which the first nucleic acid hybridizes.