CHROMOSOMAL MUTATIONS AND ASSOCIATED HEREDITARY DISEASES: ETIOLOGY AND PATHOGENESIS
Keywords:
chromosomal mutations, aneuploidy, gene dosage imbalance, meiotic nondisjunction, PSSC, reverse segregation, Down syndrome, Turner syndrome, Klinefelter syndrome, cri-du-chat syndrome, DYRK1A, chromosomal microarray analysis (CMA), prenatal diagnostics.Abstract
This article provides a comprehensive analysis of the etiology and pathogenesis of hereditary diseases caused by chromosomal mutations. Changes in chromosome number and structure — aneuploidy (trisomy, monosomy), polyploidy, deletion, duplication, translocation, inversion, and complex “de novo” structural variants (dnSVs) — lead to severe developmental defects in early embryogenesis, pregnancy loss, and congenital multisystem disorders. The article thoroughly examines etiological aspects such as meiotic nondisjunction, premature sister chromatid separation (PSSC), reverse segregation, weakening of cohesin and spindle apparatus, the effect of advanced maternal age, environmental mutagens, and genetic factors (including the high frequency of consanguineous marriages in Central Asia). It also proposes strategies for prenatal screening, genetic counseling, and disease prevention.
References
. Milani D.A.Q., et al. Genetics, Chromosome Abnormalities // StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 (last updated April 24, 2023). – PMID: 32491623.
2. Akhtar F., et al. Down Syndrome // StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 (updated December 6, 2024). – PMID: 32644692.
3. Sharma L., et al. Turner Syndrome // StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025.
4. Ajitkumar A., et al. Cri Du Chat Syndrome // StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022. – PMID: 32965943.
5. Pendina A.A., et al. Chromosomal Abnormalities in Miscarriages and Maternal Age // Cells. – 2024. – Vol. 14, Issue 1. – P. 8. DOI: 10.3390/cells14010008.
6. Gardner R.J.M., Amor D.J. Gardner and Sutherland's Chromosome Abnormalities and Genetic Counseling. – 5th ed. – Oxford: Oxford University Press, 2018. – 648 p.
7. Nishonboyev K.N., Eshonqulov O.E., Bosimov M.Sh. Tibbiy genetika: darslik. – Toshkent: O‘zbekiston Respublikasi Sog‘liqni saqlash vazirligi, 2020. – 320 b.
8. Yo’ldashev A.A., Olimova M.O. Xromosoma mutatsiyalari va uning inson salomatligiga ta’siri // Yosh olimlar ilmiy-amaliy konferensiyasi materiallari. – Andijon, 2024. – S. 16–18.
9. Jung H., et al. Complex de novo structural variants are an underestimated cause of rare disorders // Nature Communications. – 2025. – DOI: 10.1038/s41467-025-64722-2.









