Chromosomal Disorders

Introduction

Chromosomal disorders are typically those phenotypes that have changed, resulting in visible alteration caused by genetic inheritance called imprinting. However, some changes occur due to inheritance, whereas some occur in an accident while the reproductive cells are in early foetal development. There are many types of disorders affecting different parts or behaviour of a human.

Chromosomes are usually organised packages of DNA found in our body; it makes our body develop and function; typically, humans have 23 chromosomes. Each person inherits one pair of chromosomes from their mother and one pair from their father. However, these chromosomes can vary in size leading to chromosomal disorders. There are many different types of chromosomes, mainly sex chromosomes and autosomal chromosomes; they are the codes that generally contain a human’s genetic information.

So, Chromosomal disorders or any syndrome are usually characteristic of the malformations of malfunctions in the body that can be seen physically and mentally occurring due to abnormal chromosomes in number or constitution, due to deletion or addition of genetic codes.

XXX chromosome Disorder

• Trisomy of X or 47, XXX or xxx chromosome disorder is a sporadic genetic disorder to be found, which can last for years or life-long
• This genetic disorder is a characteristic of an additional X chromosome, and individuals are seen to be taller with this age. However, the chromosomal change typically causes no physical features to change
• Most of the females with this genetic disorder have normal development of sexual reproduction. The frequency of this disorder occurring is scarce and happens in only one female among 1000 newborns, where most cases are not diagnosed
• This triplex syndrome is associated with many difficulties in speech and language skills. There is also delayed development of sitting, working, and other exercises. Behavioural and emotional difficulties kidney and seizures abnormalities can also occur

Physical Signs and Symptoms of Triple X Syndrome

In this disorder, the physical as well as structural changes which can be noticeable are-

• Being taller than the average height
• Having a weak development of muscles or muscle tone is called hypotonia
• Persisting of very curved little fingers called Clinodactyly
• Having widely spaced eyes is also known as hypertelorism

Finding Triplex Disorder

• Order can be found out by doing a blood test to look for the extra presence of the X chromosome. This condition can also be found through a karyotype test or NIPT test called non-invasive prenatal testing before birth. In this process, the fluid surrounding the foetus or on the Placenta or the mother’s blood is taken and tested to find out
• After birth, the doctors can also diagnose a baby with a microarray test

Treatment of Triple X Syndrome 

Typically there is no cure for the triplex syndrome; however, treatment for the specific type of symptoms is proved to be helpful such as;

• By regularly visiting doctors

Visits to the doctor can help monitor the child’s developments, difficulties, disabilities, and health problems and get treated properly.

• Educational and support services

These types of services must be designed to help these specially-abled children with this type of disorder get educated.

• Counselling

This service can help the children understand their emotional and behavioural difficulties such as anxiety and depression and help them understand how to live a productive life.

Klinefelter Syndrome

• Chromosomal abnormalities XXY or Klinefelter syndrome is another one of the rare genetic disorders which can be found
• This condition is a medical condition that can be found in men, affecting their physical and intellectual or mental development
• In most cases, the affected individual is taller than the average height. This syndrome is not inherited and the addition of an extra chromosome during the formation of reproductive cells
• This can be found in only one in 650 newborn boys; it is one of the most common sex chromosome disorders where the changes are occurred due to the different number of chromosomes
• Different disabilities persist with this syndrome, such as depression, anxiety, lack of critical social skills, behaviour and emotional problems, hyperactivity, and an Autism spectrum disorder

Edward’s Syndrome

• Edwards syndrome is marked by low birth weight and certain abnormal features
• These include a small, abnormally shaped head, a small jaw, and a mouth—clenched fists with overlapping fingers. And heart, lung, kidney, intestine, and stomach defects

Turner’s Syndrome

• Turner’s syndrome is a genetic disorder caused due to monosomy of the X chromosome
• It is caused due to non-disjunction of sex chromosomes which takes place during gamete formation
•  The chromosomal complement of Turner’s syndrome is 44+XO, having a total of 45 chromosomes
• It was first described by H.H Turner
• The Major Symptoms of Turner’s syndrome are Female phenotype, Short stature, low posterior hairline, Secondary sexual characters, failure to develop, and Mental retardation

Down’s Syndrome

• This condition occurs when there is one extra copy of chromosome 21 in cells in the body
• It is characterised by severe mental retardation, defective development of the central nervous system, increased separation between the eyes, flattened nose, malformed ears, the mouth is constantly open, and the tongue protruding
• Down syndrome was first described by Dr John Langdon Down in 1866

Aneuploidy, Polyploidy and Euploidy

Aneuploidy is a phenomenon that occurs due to nondisjunction, resulting in the gain or loss of one or more chromosomes during meiosis. 

Polyploidy is a phenomenon in which the organisms contain more than two monoploid values or basic sets of chromosomes, i.e., -3n, 4netc.

Euploidy is obtaining or having one or more complete sets of chromosomes.

Haploid and Diploid Cells

A haploid or monoploid is a cell or organism that has just a single copy of each chromosome. Human eggs and sperms are examples.

Diploid is a cell or organism that has paired or two sets of chromosomes, one from each parent.

Physical signs & symptoms of an XXY chromosome disorder

In this XXY chromosome disorder, the physical as well as structural changes which can be noticeable are-

• Affected testicular growth
• Testicles smaller than the standard size
• Reduced muscle tone
• Reduction of body and facial hair
• Enlarged breast tissue

Finding out Chromosomal Abnormalities XXY 

The doctor can diagnose this syndrome, starting with the physical test to learn about general health symptoms. 

Then the doctors mainly conduct two types of tests: the chromosome analysis tests, also called the karyotype analysis test, where a blood test is taken to screen the chromosomes. Then there is a hormone test used to check the hormone levels in the blood or urine.

Treatment of Disorder 

Although there is no specific type of treatment to ultimately a hormone test used to check to cure a child with this syndrome, there are many ways and treatments to minimise the effects. 

1. Testosterone replacement therapy- This is one of the most common types of therapy to cure this syndrome. This therapy, although it does not improve infertility but helps in stimulating different types of physical changes in puberty. 
2. Plastic surgery: This method can be used in reducing breast tissue sizes. 
3. Educational and support services: This type of support helps the affected with Speech and physical therapy and helps them improve their social skills.

Conclusion

Although curing chromosomal disorders is not easy, it is never too late to do treatments to minimise the effects. Both the two syndromes included in this article are caused due to an addition of an X-chromosome. However, many such abnormalities occur due to the deletion or addition of chromosomes.