Medical Genetics - V. M. Zaporozhan 2005

Methods of Diagnosing Hereditary Diseases
Cytogenetic Methods

These Methods are based on The Study of the Human Karyotype. Until 1956, biologists believed that humans had 48 Chromosomes. In 1956, Swedish scientists Tjio and Levan improved the technique for studying chromosomes, which allowed them to clearly observe 46 chromosomes in the human diploid set. The Karyotyping Method they developed is still used today with minor modifications in all cytogenetic laboratories.

The main Cytogenetic methods include:

— karyotyping;

— Molecular Cytogenetic Methods;

— Determination of Sex Chromatin.



Last update: 11/08/2026

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