Human health at the cellular level
A person is happy when he or she and his or her family are healthy. The condition of a person and phenotypic traits are determined by the genotype, that is, the set of genes received from parents. And genes are DNA links that are responsible for the synthesis of proteins. And proteins are responsible for traits. Thus: chromosome → gene → protein → trait, these are the patterns that the science of genetics studies. Medical genetics is of great importance. It is she who studies hereditary diseases, the prevention of their development in ontogenesis, and the extension of human life. To do this, genetic maps are created, linkage groups and genes localized in them are established, the features of the mutation process and ways to prevent various mutations, sex-linked and non-sex-linked genes, the causes of non-disjunction of chromosomes and chromosomal rearrangements are studied.
A person is influenced by a mass of environmental factors:
- biological;
- physical;
- chemical.
4 million chemical compounds constantly act on living organisms, 6 thousand have a mutagenic effect (medicines, food additives, cosmetics, aerosols, preservatives, dyes...) The genetic load of humanity is increasing, especially after the accident at the Chernobyl nuclear power plant. Recessive and dominant genes mutate. But recessive genes manifest themselves phenotypically if they become homozygous.
Mutations: gene, chromosomal, genomic... Mutations occur in somatic cells. Mosaics appear (different eyes, white streaks in hair).
Modifications occur, and sometimes go in parallel with mutations. An example is fetal alcohol syndrome (FAS) and Dubovits syndrome...
The deeper the nature of human heredity is analyzed, the more it is implemented in the methods of diagnosis, treatment and prevention of diseases. The following methods are used in solving genetic problems:
- cytogenetic;
- biochemical;
- genealogical;
- twin;
- population-statistical;
- somatic cell genetics, etc.
Lymphocyte cultivation, differential chromosome staining, compilation of chromosome maps by karyotyping. In 2000, the human chromosome map was deciphered... The significance of this discovery: diagnosing the components of fetal diseases, early diagnosis, studying medical genetic prognosis.
Research, studying the inheritance of diseases transmitted by autosomal dominant type, autosomal recessive type, sex-linked. The concept of multifactorial diseases, enzymopathies... (examples).
Medical genetic counseling is of particular importance in the prevention of hereditary diseases, aimed at identifying a sick child in the family. Modern methods for prenatal prenatal diagnosis of hereditary diseases:
- ultrasound (echography);
- amniocentesis method;
- fetoscopy;
- method for determining -fetonfotein;
- chorionic villus biopsy.
Thus, one of the tasks of medical genetics is fulfilled by the methods of prenatal diagnosis - preventing the birth of children with severe hereditary or congenital pathology.
Methods of prenatal diagnosis are constantly being improved. In the near future, fetal cells and maternal blood will be obtained. About 1 fetal cell per 1 million maternal cells circulate in the blood of a pregnant woman.
The isolation of such cells will eliminate invasive interventions for the fetus. Recently, new methods of diagnosing hereditary diseases have been developed, in particular the method of biological microchips.
The use of biotechnology methods to obtain drugs, artificially synthesized genes outside the body, gene deletion, gene transplantation, somatic cell hybridization (hybridomas of cancer cells and lymphocytes)... Areas of biotechnology: cell engineering and genetic engineering. (cloning).