Monogenetic inheritance are genetic conditions that arise from the mutation of a single gene and are generally inherited in a specific pattern. When a physical characteristic is dominated by a single gene, its properties will be subject to the characteristics of the alleles. For the physical attributes that are subject to a single gene, when it has more than two types of alleles, it is possible to determine the probability that each allele has of being transferred to the offspring.
Monogenetic inheritance is the cause of the manifestation of the following diseases:
- Autosomal Dominant Inheritance: this determines that the individual only requires one abnormal gene, from one of the parents, to receive the disease. In this case, it is enough for a single abnormal gene to be present on one of the chromosomes of either parent to cause the disease, even when the parallel gene from the other parent is natural.
Certain criteria must be met for a disease to be transferred by the autosomes and to proceed in a dominant way: that the character manifests itself in each generation. That the two sexes get affected equally. The person who does not present the genetic alteration does not transfer the character. Among the dominant inherited diseases is neurofibromatosis.
- Autosomal recessive inheritance: there are certain diseases that are transferred in a recessive way. This means that a person must inherit two mutated copies of a single gene (one copy from the mother and one from the father) to get the disease. Now, if the person inherits a normal copy of the gene and a mutated one, the person will have a greater chance of being healthy, but will be a carrier since the normal copy of the gene will compensate for the mutated one. Among the inherited diseases of a recessive nature are: sickle cell anemia, cystic fibrosis and Tay-Sachs disease.
- Inheritance added to the X chromosomes: it is good to mention that women have two copies of the X chromosome (XX), which means that if any of the genes of said chromosome comes with an alteration, the other that is normal, will compensate the copy that is altered, causing the woman to be healthy, but a carrier of the condition associated with the X chromosome.
Men, on the other hand, have an X and a Y chromosome (XY), so if any of the genes that make up the X chromosome undergoes some variation, it will not have another copy that compensates for it, this means that the probability transmission of the disease is extremely high. Some of the diseases related to this inheritance are: muscular dystrophy and hemophilia
