Abstract

Cytogenetics is the study of structure and behavior of chromosome at a macroscopic level. Various cytogenetic techniques can detect different numerical such as aneuploidies and abnormalities in chromosomal structure such as Duplication, Deletion, Translocation, Inversion, Insertion and Copy Number Variations (CNVs) etc. Scientific and technical advancements from conventional cytogenetics to molecular cytogenetics in the field of medical genetics have brought improvements in the resolution of chromosome analysis facilitating a deeper understanding of chromosomes, structurally and functionally. Shift in cytogenetics to chromosomics has helped in understanding the influence of three-dimensional dynamic structure and function of chromosomes on gene expression and genome evolution by integrating cytogenetics with genomics and cell biology. This evolution in cytogenetics has made the possibility of not only postnatal diagnosis of chromosomal abnormalities but is also responsible for the advent of prenatal chromosomal disorders’ diagnosis and genetic counseling in clinical medicine. Now it is our aim to make aware our patients about these available advanced tests and make available these tests to our patients at low cost. This incredible journey from symptomatic disease to conventional karyotype to molecular cytogenetic to chromosomics (genotype) should be continued in the future for the futuristic genetic evolution. This review article talks over the evolution and advancements in cytogenetic techniques covering a brief overview of conventional Karyotyping and FISH and discussing in detail about molecular cytogenetics advanced techniques like Multiple Ligation Dependent Probe Amplification (MLPA), Quantitative Flourescent-Polymerase Chain Reaction (QFPCR), Chromosomal microarray and Optical Genome mapping.

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