The origin of the human karyotype: its uniqueness, causes and effects

  • Abyt Ibraimov Laboratory of Human Genetics, National Center of Cardiology and Internal Medicine, Bishkek, Kyrgyzstan
Keywords: human karyotype, chromosomal Q-heterochromatin, human adaptation, human evolution.


As is known, the diploid number of human chromosomes is 46, while in other higher primates, such as chimpanzees and gorillas, this number is 48. It has been established that a decrease in the number of chromosomes by two in humans is a result of the fusion of two autosomes into one chromosome in his karyotype ancestors. However, why such changes in chromosomes occurred among the highest primates in humans, their uniqueness, causes and consequences have not yet become the subject of special studies. We believe that the transition from 48 to 46 chromosomes, as well as changes in the composition, localization and amount of chromosomal heterochromatin regions in the karyotype of the ancestors of modern man turned out to be crucial in his formation as a biological species with all the ensuing consequences.


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