From Big Medical Encyclopedia

KARYOLOGY (grech, karyon nut, a kernel of nut + logos the doctrine) — the section of cytology studying a structure, function and evolution of a cellular kernel and its structures. Emergence To., occurred at the end of 19 — the beginning of 20 century, it is caused by a role of a kernel in vital processes of a cell, especially in the phenomena of heredity (see. Cell , Kernel of a cell ). V K. use methods optical and a submicroscopy (see. Microscopic methods of a research ), cytochemistry (see), autoradiography, etc. Use of these methods allowed to establish a structure and behavior of nuclear structures (chromosomes, a kernel, a nuclear envelope) in not sharing cell and at various forms of cellular division — amitotic division (see), mitosis (see), meiosis (see) and endomitosis. Special value in To. got studying of a structure and patterns of reproduction chromosomes (see). The research of chromosomal complements of cells of the person and animals is normal also of pathology, become possible in connection with development of a method of an indirect research of chromosomes in culture of peripheral blood, allowed to establish an origin of group of the diseases of the person connected with change of quantity or the structure of chromosomes which received the name chromosomal diseases (see).

The problem of genetic activity of separate chromosomal loci and mapping of chromosomes, in particular chromosomes of the person is actively studied.

Kariologichesky researches established change chromosomal complement (see) in cells at action of various mutagens (see). Especially widely apply kariologichesky researches in oncology. In particular, it is established that in cells of tumors there are sharp deviations of number and structure of chromosomes. The research of chromosomal complement of cells of the person is widely used in differential diagnosis of hereditary diseases of the person (see. Hereditary diseases ).

Special direction K. the kariosistematika is, edges investigates patterns of evolutionary transformation karyotype (see), studies the Karyotype as a taxonomical sign, develops criteria of specific independence. Chromosomal complement is the important sign allowing to establish interpopulation and even specific differences at phenotypical similar types, and comparison of chromosomal complements allows to track in some cases bonds between populations, close types etc.

See also Cytology .

Bibliography: V. N. Kariosistematik's eagles of mammals, M., 1974, bibliogr.; Fundamentals of cytogenetics of the person, under the editorship of A. A. Prokofieva-Belgov-skoy, M., 1969; The Guide to cytology, under the editorship of A.S. Troshin, t. 1 — 2, M. — L., 1965 — 1966.

T. A. Zaletayeva.