Generality
The karyotype is a test that allows to study the number and / or structure of an individual's chromosomes. The purpose of this "analysis is" to identify any anomalies responsible for various diseases, hereditary or not.
The karyotype examination is performed on a sample of venous blood taken from the arm or on the cells collected through a needle aspiration of the hematopoietic marrow. In pregnant women, however, the evaluation of the fetal chromosomal structure can be performed on a sample of amniotic fluid. or chorionic villi.
What's this
The karyotype is the analysis of chromosomes. These elements are present in the cell nucleus.
The chromosomes contain the genetic patrimony of an individual and on their structure are found, in linear succession, the genes.
Genes represent the "fundamental unit of" genetic information: genes are, in fact, made up of traits of hereditary material, DNA, that is the molecule that contains all the information necessary for the "construction" of the individual (with inherited physical characteristics of the person to the directives for the growth, development and functioning of the whole organism).
Chromosomes are found in all cells of the body in a fixed number: as a rule, in the human species there are 46, of which 44 autosomes and 2 sex chromosomes, identical in the female (XX) and different in the male (XY).
The karyotype analysis allows to highlight, by examining the blood cells, the anomalies of number (such as trisomies and monosomies) and structure (translocations, deletions, inversions, etc.) affecting the chromosomes.
Any chromosomal changes can cause birth defects and birth defects, repeated miscarriages, or other types of conditions (such as blood and lymphatic system disorders).
