There are several types of diseases that can be transmitted from parents to children through gametes. These are the diseases known as genetic or hereditary. Most of these have no relation to sex, since it is in the autosomes where the genes that encode them are located.
All diseases are considered genetic which can be perpetuated for generations by their parents, even if they do not promote manifestation. Among the most common examples, it is possible to highlight color blindness and hemophilia.
However, the cases do not stop there. It is estimated that the number of genetic diseases cataloged in the human race exceeds 3,500 variations and constantly new types appear and challenge medicine.
Heritage
Most of these diseases are inherited independently of sex, since the coding does not occur in heterochromosomes, but in autosomes. Such an inheritance has numerous possible ways of occurring, as Mendelian laws are always followed. Thus, there are situations in which genes are linked (linkage), polygeny, among others.
The severity of a genetic anomaly, depending on the case, can be considered harmless or lethal. Polydactyly, for example, is a genetic disorder which allows its carrier to have a life without complications, since it consists of leaving it with more than five fingers.
Genetic diseases can affect only a certain area, such as polydactyly, but they can also give rise to a group of several anomalies distributed throughout the body.
Photo: Reproduction
Origin of these problems
The diseases considered genetic can be caused by several causes, among which we can list: the genes transmitted from parents to children who may be defective; anomalies during reproduction, which cause discrepant chromosome separation; depending on the environment, also the activation of latent genes, which are capable of giving rise to a disease; the exposure of the fetus, during pregnancy, to factors that cause changes in genes, such as chemical components and radiation.
The symptoms of genetic abnormalities are identified in a simple and remarkable way. However, there are cases in which it is necessary to verify by means of complementary verification factors, such as the karyotype check, a process responsible for identifying possible anomalies in the chromosomes such as the duplication of one or even the absence of parts of another. Biological and chemical analyzes of fluid samples or specific research with the individual’s DNA material are also valid.
Combating these anomalies
The most suitable and effective fight against genetic diseases is the prevention mechanism, either through prenatal diagnosis or genetic guidance. Once manifested, a genetic anomaly becomes complex to fight.
Promoted by various techniques, prenatal diagnosis aims to identify serious diseases before the individual’s birth. Genetic guidance (counseling) is based on the analysis of genetic diseases in a family group and the way in which they have been distributed. Thereafter, a calculation is performed to have the probability of heredity to other descendants.
