Cytogenetic study in hematological malignancies

1. The Cytogenetic study in Hematological malignancies Muhammad Jamil Cytogeneticists

2. Introduction 1.Cytogenetic is a branch of pathology and genetics concerned with the study of normal chromosomes and chromosome aberrations. Classical cytogenetic allows microscopic visualization of whole chromosomes in order to assess their number and structure. 2.The study of chromosomes, which are long strands of DNA and protein that contain most of the genetic information in a cell. Cytogenetic involves testing samples of tissue, blood, or bone marrow in a laboratory to look for changes in chromosomes, including broken, missing, rearranged, or extra chromosomes.

3. What Is a Cytogenetic study • Cytogenetic involves testing samples of tissue, blood, or bone marrow in a laboratory to look for changes in chromosomes, including. • Broken. (Deletion) • Missing. (Monosomy) • Rearranged. (Translocation) • Extra. (Trisomy) • Changes in certain chromosomes may be a sign of a genetic disease or condition or some types of cancer. • Cytogenetic plays a key role in the detection of chromosomal abnormalities associated with malignancies, as well as the characterization of new alterations that allow more research and increase knowledge about the genetic aspects of these diseases.

4. What is a chromosome • Chromosomes are thread-like structures present in the nucleus, which carries genetic information from one generation to another. They play a vital role in cell division, heredity, variation, mutation, repair and regeneration. • DNA present on the chromosome not only carries most of the genetic information but also controls the hereditary transfer. Chromosomes are essential for the process of cell division, replication, division, and creation of daughter cells.

5. Types of chromosome There are four main types of chromosomes: Metacentric. Sub metacentric. Acrocentric. Telocentric. Chromosomes are found within the nucleus of most living cells and consist of DNA that is tightly wound into thread-like structures.

7. The Cell Cycle • The Cell cycle has the following phases. • Interphase. • Gap phase(G1) • Synthesis phase (S) • Mitotic phase (M)

8. Stages of Cell Cycle

9. Mitosis • Mitosis is a continuous process that usually lasts 1 to 2 hours but for descriptive purposes it is convenient to distinguish five distinct stages. These are • Prophase • Prometaphase • Metaphase • Anaphase and telophase

10. Metaphase • The chromosomes become aligned along the equatorial plane or plate of the cell, where each chromosome is attached to the centriole by a microtubule forming the mature spindle. • At this point the chromosomes are maximally contracted and therefore , most easily visible. Each chromosome resembles the letter X in shape ,as the chromatids of each chromosome have separated longitudinally but remain attached at the centromere.

11. Methods of Chromosome Analysis • Cell culture • Colcimed treatment or metaphase arrest • Cell harvesting • Chromosome Preparation on the Slide • Ageing of chromosome • Chromosome Banding • Karyotype Analysis or Interpret of result

12. 1.Chromosome Preparation • Most commonly circulating lymphocytes from peripheral blood are used. • Samples for chromosomal analysis can be prepared relatively easily using. • Blood. • Skin. • Bone marrow. • Chorionic villi. • Amniotic fluid.( Aminiocytes) • Any tissue with living nucleated cells that undergo division can be used for studying human chromosomes.

13. Fetal and Neonatal blood samples in which problem may be encountered

14. Patient History is Mandatory • Types of test • Cytogenetic study test technique different. • Blood • Bone marrow • Cultures • Correlation with patient • Treatment of patient

15. What is Chromosomal Banding? • A part of chromosome which is clearly distinguishable from its adjacent segments by appearing darker or lighter with various banding methods.

16. Chromosomal Band

17. Chromosomal Banding Techniques • G-Banding. • R-Banding. • Q-Banding. • C-Banding.

19. G-banding • G-banding generally provides high quality chromosomes analysis with approximately 400-500 bands per haploid set. • Each of these bands corresponds on average to approximately 6000-8000 kilobases(kb) of DNA. • This involves first inhibiting cell division with an agent such as methotrexate or thymidine. • Folic acid or deoxycytidine is added to the culture medium,releasing the cells into mitosis.

20. Karyotype Analysis or Result interpret • The next stage in chromosome analysis involves first counting the number of chromosomes present in a specified number of cells, sometimes referred to as “Metaphase spreads”. • The banding pattern of each chromosome is specific and can be shown in the form of a stylized ideal karyotype known as an Idiogram.

22. Cytogenetic Room

23. Sample Processing

24. Sample processing

25. Microscopy

36. What is hematological malignances • Hematologic malignancies are cancers that affect the blood, bone marrow, and lymph nodes. • This classification includes various types of leukemia. • ALL • CLL • AML • CML • Hodgkin’s Lymphoma • Non Hodgkin’s Lymphoma

37. Role of cytogenetic study in Hematological malignances • Chromosome analysis has become a critical aspect in the workup of hematopoietic neoplasms. Information obtained from cytogenetic studies is used on a clinical basis for diagnosis and prognosis as well as a research basis for gene identification and potential treatment advances. • Strikingly, cancer cytogenetic not only provides key information to improve the care of patients with leukemia and various cancers but also acts as a guide to identify the genes responsible for the development of these neoplastic states.

38. Common Chromosomal abnormalities

39. Cytogenetic study • Diagnosis • Prognosis • Monitoring the Treatment response • Remission • Relapse • Good prognosis • Bad prognosis

40. Thank you