- April 29, 2020
Accordingto (Ahmed, 2015), a karyotype is a set of a number, size, and shapeof chromosomes present in the cell nuclei of an organism and theirphysical appearance. The physical appearance and the numbers of thesechromosomes vary depending on the type of species under study. Inessence, Karyotyping is the close analysis and interpretation ofchromosomes to determine chromosomal abnormalities that can be linkedor related to various genetic diseases and types of cancer in theworld. A karyotype is some chromosome present in the cell nuclear,and the formation of chromosomes involves different stages.
Thechromosomal structures in all human karyotype are organized intoseven categories which are dependent on the size of their bands afterthe completion of the staining procedures. During banding whichinvolves mitosis as a process, the 23 pairs of human chromosomesundergo condensation process which makes it possible for them to bevisualized under a light microscope. Also, the karyotype analysis isnever complete without blocking the cells in mitosis and the use ofGiemsa dye.
Duringthe Karyotype construction, the following method is helpful: thespecimen which in this case comes from different cells in the bodysuch as the white blood cells, amniotic fluid or the skin cells isprepared to enter into the mitosis stage. The cells join at themetaphase stage. Moreover, the preparation of the cells entailstreating the specimen using trypsin and staining it so that a bandingpattern can take place. Images are then taken using a camera attachedand sent directly to a computer to process and generate karyotypes.The karyotypes are then later used to determine if an adult understudy has abnormalities or defects which a child can inheritgenetically. This method is reliable and more accurate. It allows forthe detection of microdeletions at early stages.
Inthis test, I’m going to carry out three patients’ (Patient A, B,and C) case history. I will complete their karyotypes and diagnoseany missing chromosome or extra chromosomes if any.
PatientA is a 40-year-old lady (female) with a nearly full-formed fetus. She has a total number of 47 chromosomes in the identified karyotype.My patient has XX chromosomes and therefore indicating she is afemale since a large and small one shows a male gender. Chromosomeset 21 has an extra chromosome. Therefore I can diagnose that mypatient is suffering from Down syndrome.
PatientB is a 28-year-old male who happens to be infertile. The totalnumber of Chromosomes available on the identified karyotype is 47.This patient has XXY sex chromosome with an extra set of thechromosome in X. Therefore his notation is 47 X_XY. Diagnose for thispatient is Klinefelter`s Syndrome.
Lastly,Patient C history is that he died shortly after birth. The totalnumber of chromosomes available in the identified karyotype is 47. Mypatient has a sex chromosome of XY with chromosome set 13 having anextra. The correct notation for this patient’s karyotype is 47 XY+13 therefore my diagnosis is that this patient had Trisomy 13Syndrome.
Inconclusion, Karyotyping is imperative as it helps in detectingabnormalities and defects that may arise due to a cell lacking achromosome or having extra chromosomes which can lead to variousgenetic diseases and development of some cancerous cells.
Ahmed,N. T. (2015). Karyotype Analysis Activity. TheAmerican Biology Teacher, 77(1),63-67.