- 1. The process of breeding a hybrid. 2. Crossing over between related but nonallelic genes. 3. The specific reassociation of complementary strands of polynucleic acids; e.g., the formation of a DNA-RNA hybrid. 4. The process or act of forming a macromolecular hybrid in which the subunits are obtained from different sources. SYN: crossbreeding.- DNA h. a technique used to determine the relatedness of microorganisms by the speed and efficiency of the reassociation of single-stranded DNA to form double-stranded DNA when one of the strands originates from one organism and the other strand from another organism; occurs when the base sequences are complementary or nearly so.- fluorescent in situ h. a method used to determine the chromosomal location or expression pattern of genomic DNA or cDNA fragments. The piece of DNA to be mapped (the “probe”) is labeled with a fluorescent dye and hybridized to a chromosome preparation or to a tissue section. The probe anneals to complementary DNA or RNA sequences. Examination of the chromosomes or tissue section under a fluorescence microscope reveals the number, size, and location of the target sequences. SYN: fluorescence in situ h..- overlap h. SYN: chromosome walking.- in situ h. a technique developed in 1969 for annealing nucleic acid probes to cellular DNA for detection by autoradiography. Under proper laboratory conditions, the binding process occurs spontaneously. In situ h. constitutes a key step in DNA fingerprinting. SYN: in situ nucleic acid h..- in situ nucleic acid h. SYN: in situ h..
* * *hy·brid·iza·tion (hi″brid-ĭ-zaґshən) 1. the act or process of producing hybrids. 2. nucleic acid h. 3. in chemistry, a procedure whereby orbitals of intermediate energy and desired directional character are constructed by taking an appropriate linear combination of atomic orbitals; e.g., sp3 hybrid orbitals are formed from one s and three p orbitals.
Medical dictionary. 2011.