1 / 4

Genetic Disorders

Normal Karyotype = Study of chromosomes Human somatic cells contain 46 chromosomes22 homologous pairs of autosomes and two sex chromosomes, XX in the female and XY in the maleProcedurechromosome spread in metaphasearrest mitosis in dividing cells in metaphase by the use of mitotic spindle inhib

beth
Download Presentation

Genetic Disorders

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

    1. Genetic Disorders

    2. Normal Karyotype = Study of chromosomes Human somatic cells contain 46 chromosomes 22 homologous pairs of autosomes and two sex chromosomes, XX in the female and XY in the male Procedure chromosome spread in metaphase arrest mitosis in dividing cells in metaphase by the use of mitotic spindle inhibitors (e.g., colcemid) In metaphase spread, the individual chromosomes take the form of two chromatids photographed or imaged stained MC stain for chromosomes - Giemsa stain (G banding ) Nomenclature Male with trisomy 21 is designated 47,XY,+21 Short arm of a chromosome - p (for petit), & long arm - q (the next letter of alphabet) Chromosomal segment located on the short arm of the X chromosome, in region 2, band 1, and sub-band 2-Xp21.2

    3. Normal Karyotype

    4. FISH =Fluorescence in Situ Hybridization Major limitations of karyotyping applicable only to cells that are dividing micro deletions, complex translocations, and telomere alterations not readily detectable by routine karyotyping Procedure (FISH) Probes are labeled with fluorescent dyes and applied to interphase nuclei Spectral karyo typing (SKY) combination of five fluorochromes and appropriate computer-generated signals Recent FISH application Tumor-specific alterations in gene copy number can be ascertained Compares the DNA content of normal and tumor cell populations

More Related