Winter Internship

Karyotyping is a laboratory technique used to analyze and visualize the number, size, and shape of an individual’s chromosomes. It involves arranging and matching chromosomes from a cell sample into pairs, known as homologous pairs, based on their size, centromere position, and banding pattern. This technique provides a snapshot of an individual’s chromosomal composition, helping to identify any abnormalities, such as aneuploidy (abnormal chromosome number) or structural variations. The lab I worked in was fully equipped with an automated cytogenetic imaging system with metaphase finder. I was able to learn about the following steps under the supervision of Dr Poonam Jain.

• Sample Preparation: A bone marrow or blood sample is collected from the patient. The sample is then treated to encourage cell division, leading to the formation of metaphase cells, which are cells in the process of cell division with visible and distinguishable chromosomes.
• Metaphase Spreading: The cell sample is cultured and treated to arrest cell division at the metaphase stage. This ensures that the chromosomes are maximally condensed and visible.
• Automated Imaging: An automated cytogenetic imaging system is employed to capture high-resolution images of the metaphase cells’ chromosomes. This system is equipped with a metaphase finder, which automatically identifies and selects cells that are most suitable for karyotyping analysis.
• Chromosome Analysis: The software within the imaging system analyzes the images, identifying and classifying chromosomes based on their size, shape, and banding pattern. This allows for efficient and accurate chromosome pairing.
• Abnormality Detection: The automated system identifies any chromosomal abnormalities, such as translocations, deletions, or inversions, which are common in leukemia cases.
• Karyotype Generation: Based on the analysis, the system generates a karyotype – a visual representation of the patient’s chromosomes arranged in homologous pairs. Any abnormalities are highlighted, providing valuable diagnostic information.
• Clinical Interpretation: The generated karyotype is reviewed by a cytogeneticist or medical professional to interpret the results. They determine the significance of any observed abnormalities and how they might relate to the leukemia diagnosis or prognosis.

Fluorescence In Situ Hybridization (FISH) is a molecular biology method that uses fluorescent probes to pinpoint and visualize specific DNA or RNA sequences within cells. It helps researchers study genetic information’s location and quantity in cells, aiding genetic research, cancer diagnosis, and clinical genetics. FISH is valuable for observing chromosome structure, gene activity, and abnormalities. It’s a key tool in genetics and medical research, enabling direct visualization of genetic material within cells.