The first thing we are going to do to know the meaning of the term deletion is to determine its etymological origin. In this case we can state that it is a word that derives from Latin, specifically, it is the result of the sum of the following components of said language:
-The verb “delere”, which can be translated as “delete”.
-The suffix “-tus”, which is used to indicate the person who has received the action.
-The suffix “-cion”, which is used as a synonym for “action and effect”.
This concept, used in the field of biology , is used to name a genetic alteration that occurs when the deoxyribonucleic acid ( DNA ) sequence loses one nucleotide or more.
It should be remembered that DNA is a biopolymer whose sequence houses the information necessary to carry out protein synthesis, constituting the genetic material present in cells . A nucleotide , for its part, is an organic compound that has phosphoric acid, a sugar and a nitrogenous base.
Deletion, in short, involves the loss of a part of the DNA found in a chromosome . That is why it is said to be a chromosomal mutation. By modifying the genetic structure, the deletion causes an imbalance.
Deletions can be caused by a failure in the crossing of chromosomes, by an abnormality in the offspring, or by a break in the chromosome. Depending on the sector where the chromosomal alteration occurs and the type of breakage, it is possible to differentiate between different types of deletions.
Distal deletion occurs when the lost DNA fragment is close to the telomeres. In the proximal deletion , however, the mutation takes place near the centromere . If the chromosome breakage occurs at two points, an interstitial deletion is generated; On the other hand, if there is only one break, it is called a terminal deletion .
Among the possible consequences of a deletion are Phelan-McDermid syndrome (a delay in language , learning and motor skills), Angelman syndrome (linguistic, motor and developmental problems) and Prader-Willi syndrome ( poor growth, intellectual disability and psychomotor problems).
In the same way, we cannot ignore another important series of syndromes that occur as a consequence of a deletion. We are referring to the following:
-Wolf-Hirschhorn syndrome, which is also known as 4p deletion in reference to the fact that it affects precisely chromosome 4. It is characterized because the person who suffers from it suffers from defects in the scalp to intellectual disability, including epilepsy, palate cleft and a notable delay in bone development.
-Cat meow syndrome, which is also called 5p deletion because it affects chromosome number 5. Newborns who suffer from it are identified because they have a cry similar to the meow of said animal, because they are born with low weight, because they have the base of the nose is very wide and because they present with a very round face and eyes very far apart. To all this we must add that they also suffer from microcephaly.