Epigenetics changes of activity of the ribosomal cistrons of acrocentric chromatids in fetus, middle age (25–40 years) and old individuals (88–106 years) - T. Lezhava; T. Buadze; D. Monaselidze; T. Dzhokhadze; N. Sigua; N. Dzhangulashvili; M. Gajozishvili; M. Koridze; N. Zosidze; M. Rukhadze (Cytology and genetics, 2020)