Molecular cytogenetic is a discipline which increases the diagnostic value and enlarges the scope of routine chromosome analysis with using molecular biology and cytogenetic techniques together. Molecular Cytogenetic involves effective and rapid methods to detect chromosome abnormalities with multi-colored DNA probs which may not diagnosed with conventional cytogenetic. FISH and SKY techniques are used routinely in our Molecular Cytogenetic Department.

FISH (Fluorescence In Situ Hybridization)FISH (Fluorescence In Situ Hybridization):

FISH (fluorescence in situ hybridization) is a cytogenetic technique that is used to detect and localize the presence or absence of specific DNA sequences on chromosomes. FISH uses fluorescent probes that bind to only those parts of the chromosome with which they show a high degree of sequence similarity. Fluorescence microscopy can be used to find out where the fluorescent probe bound to the chromosomes. FISH can also be used to detect and localize specific mRNAs within tissue samples.




Fiber-FISH:

Fiber-FISHFluorescence in situ hybridization to DNA fibers (Fiber–FISH) is a high-resolution, wide-ranging physical DNA mapping method that finds increasing application in the study of pathological gene rearrangements. Fiber FISH provides a higher resolution of analysis than conventional FISH and yields more precise information as to the localization of a specific DNA probe on the chromosome.





Spectral Karyotyping (SKY)Spectral Karyotyping (SKY):

SKY is a powerful 24-color, whole-chromosome painting assay that allows the simultaneous visualization of each chromosome in different colors. Five spectrally distinct dyes are used in combination to create a cocktail of probes unique to each chromosome. SKY can detect chromosomal material of unknown origin, complex rearrangements, translocations, large deletions, duplications, aneuploidy, and more.







CGH (Comparative Genomic Hybridization)CGH (Comparative Genomic Hybridization):
Comparative genomic hybridization (CGH) is a molecular cytogenetic method for the analysis of copy number changes (gains/losses) in the DNA content of a given subject's DNA and often in tumor cells.
CGH will detect only unbalanced chromosomal changes. Structural chromosome aberrations such as balanced reciprocal translocations or inversions cannot be detected, as they do not change the copy number.