What are genetic syndromes?
Genetic diseases or syndromes, according to theChildren’s Minnesota organization, are those that generate a disorder due to the alteration of a gene. These genes are what supply information to our body, to determine who we are.
The serious alterations manage to make the instruction of the only gene do not make sense in our body, so it is not executed and we present discrepancies in our body.
Similarly, genetic syndromes cannot be predicted or prevented, but in some cases they can be identified and tested to confirm diagnoses.
Causes of genetic syndromes
The nature of genetic syndromes has certain reasons that constitute their presence. They are the reason for their origin and these will then be described for your further understanding.
Mutations consist of repeated sequences interfering with gene expression. In general terms, the mutation can be inherited or acquired. Mutations can range from hair color to the development of diseases or health problems.
In addition, genetic mutations affect depending on which is the committed pair, if the recessive or the dominant.
If it is the dominant gene, the unaffected gene pair will be disabled and the disorder involved will develop, but if it is the recessive gene, the individual is known as a “carrier” but does not suffer any direct consequences.
Trisomy is defined as the presence of an extra chromosome, within a conjugation of a diploid organism. Instead of presenting two copies, as would be the recessive and dominant gene, they present three pairs, producing from this extra gene, developmental modifications both physically and cognitively.
In a Baptist Health article , they explain that trisomy can occur with any of the 23 pairs of chromosomes, but is usually common with pairs 21, 18, and 13. In fact, in data collected in the United States, regarding control and disease prevention, it was revealed that these trisomies occur in 1 in 691 births.
loss of genetic material
Loss of genetic material is a Deletion-type chromosomal abnormality , where segments of the chromosome are missing in a small amount of material. From this, syndromes such as Angelman, Prader-Willi and Cri Du Chat are produced.
They are rarely detected before birth, and involve both physical and intellectual congenital conditions, affecting not only one genetic pair but also, in some cases, contiguous ones.
Disorders presented through inherited genes are present from the parent’s egg or sperm, depending on who is the carrier.
The risks are increased when there are two or more pathological cases present in the family branch, presenting mainly cases of schizophrenia or heart failure at a very early age.
Most common syndromes of human genetics
Among the types of genetic syndromes that can occur, there are some that are the most common to develop. They will be described below for their identification and recognition.
1. Down syndrome
Down syndrome is an alteration due to the presence of an extra chromosome, which is specifically a third pair in pair 21, which would be known as trisomy 21.
It is a cause of intellectual disability affecting braindevelopment, and is one of the most common human genetic alterations. It is of unknown cause but occurs during pregnancy, and the risk increases under the following circumstances in pregnancy:
- elderly mother
- The parents are carriers of the genetic translocation
- Having other children with Down syndrome
Among the complications that individuals with this genetic translocation may present are heart disease, immune system disorders, obesity, hearing problems, vision, low nasal bridge, among others.
By the year 2010, success was obtained in the application of a determination of the syndrome by analyzing the blood of the pregnant mother so that through the small piece of DNA that transits in her blood belonging to the embryo, her genetic conditions are analyzed.
2. Patau syndrome
Patau syndrome is also a trisomy but of the chromosomal pair 13. It is one of the least frequent to present and is not inherited. It translates into several serious alterations in the body, both anatomical and functional, and most fetuses do not reach term when presenting it.
An ultrasound could detect in time the anatomical malformations present in the fetus, and at the culmination of the gestation process, genetic tests are performed trying to determine the cause, to prevent a next child from presenting the same conditions.
Among the various existing symptoms could be highlighted: cleft lip, hernias, mild intellectual disability, seizures, small eyes, among others.
3. Edwards syndrome
It is a genetic disorder that involves an extra chromosome of pair 18. It presents characteristically with low birth weight, small head and mouth. This syndrome increases the risk of developing cancer and they are not even born.
In the study entitled ” Edwards Syndrome: Trisomy 18 “,it is explained how this syndrome presents conditions in cardiac, cranioencephalic, musculoskeletal and neurological malformations. They limit the quality of life of the patient and usually require treatment and even medical equipment in their development throughout life.
4. Turner Syndrome
Turner syndrome is a syndrome that directly affects the development of girls. They usually present height problems and correct functionality in the reproductive area.
It can be treated with growth hormones , if it is detected in time and although physiologically they present various symptoms, they do not usually have medical complications with the advancement of technology throughout the 20th century.
Women usually have one pair of “X” chromosomes, but those with Turner syndrome only have one. There are even girls who are born with the disorder in only some of their cells, not all, so the symptoms are milder.
With symptoms we refer to the following:
- drooping eyelids
- Moles in greater quantity
- abnormal bone development
- Lack of breast development at the expected age
- Learning problems
5. Klinefelter syndrome
Klinefelter syndrome would be the counterpart of Turner syndrome, a boy being born with an additional copy of the X chromosome. It affects the size of the testicles and the production of testosterone.
The severity increases when beyond being chromosomally “XXY”, children are born with two or even more chromosomes, such as “XXXY” which would complicate the symptoms and could cause other health problems.
The symptoms that fit within this disorder are the following:
- weak bones
- Little Energy
- Small penis and testicles
- Tall stature and little muscle
- delayed puberty
6. Prader Willi Syndrome
In an OrphanetScientific articleonPrader Willi syndrome , it is explained how this is a very rare disorder and is caused by the partial deletion of chromosome 15. It is rare and brings with it behavioral problems, short stature and mild intellectual disability .
It includes a risk of obesity, during the development of childhood and adulthood, being multisystemic and of complex rarity in embryonic development.
7. Fragile X syndrome
This syndrome is defined as one of the most common ways in which intellectual disability occurs, even produces speech delay,anxietyand hyperactivity.
The disorder is known as FXS because of its acronym in English, and affects both men and women, but in women the symptoms are much milder than in men because it is a single-gene syndrome. Among these symptoms we find:
- Developmental delay
- Behavioral problems
- Learning disability
8. Cri-du-Chat Syndrome
The name of this syndrome in Spanish has been: Cat meow syndrome. In the scientific article on theCri Du Chat Syndrome: a rare chromosopathy , it is explained that the associated name is due to the fact that his crying is affected by an abnormal development of the larynx due to chromosomal conditions that imply its partial elimination.
This syndrome is diagnosed a few days after birth, the cry being much more acute and the affected chromosome is pair 5. This being the main gene that is affected, it also influences neuronal migration and brain development. They may also present psychomotor retardation and cardiac abnormalities or conditions.
9. Double Y syndrome
It is also known as Jakob syndrome and consists of an extra “Y” chromosome in men, that is, instead of “XY” it is “XYY”. There are difficulties in oral language, coordination and behavior, even more so, they can carry out a satisfactory sexual life being fertile and productive.
Among the prominent symptoms found are:
- Above average height
- Muscle weakness
- Curved fingers
- cystic acne
10. Pallister Killian syndrome
Pallister Killian syndrome is diagnosed prenatally, is not hereditary, and is rare. In a clinical report titled“Killian-Pallister Syndrome. Report of a case in interdisciplinary rehabilitation therapy“, it is explained how its manifestations consist of phenotypic traits including short neck, alopecia, severe mental retardation, seizures.
In obstetric supervision exams, the diagnosis must be made if necessary for correct knowledge. The presence of serious malformations, during the embryonic development process, will be of determining rank for attribution to this syndrome.
11. Cystic fibrosis
It is a genetic disease that is usually hereditary and consists of excessive production of thick mucus, which leads to problems both in the lungs and in other organs.
Chromosome 7 is responsible for this pathology and affects variable severity. In many cases, it produces infertility in men, due to obstruction or maldevelopment of the duct, and in women it also means a problem but with a lower complication rate.
Symptoms include infections, constipation or diarrhea, sweating, coughing up thick phlegm, wheezing, and others.
12. Gilford syndrome
It is a rather strange genetic disease, which consists of premature aging in infants. Alterations and mutations occur, where even the integrity of some organs is compromised, weight loss, hair loss, the appearance of wrinkles and spots on the skin occur.
Gilford syndrome is also known as Gilford progeria, and it even affects death due to heart conditions that people usually present during adulthood, plus their aging is usually phenotypic and the rest of their different organs remain healthy and functioning. correctly.