Chromosomal Abnormalities

Chromosomal Abnormalities

In the nucleus of each, the DNA molecule has thread-like structures called chromosomes. A chromosome is a carrier of genetic information and is made of DNA tightly coiled together several times over proteins called histones that help support its structure. 

A set of chromosomes is known as a karyotype. When there is any deviation from the normal karyotype, it is known as a chromosomal abnormality. It affects the number of chromosomes, the structure of chromosomes, or the composition of chromosomes. While some of these abnormalities are harmless, others can be associated with clinical disorders. It is the reason for half the spontaneous abortions. 

The most severe chromosomal abnormalities are caused by the loss or gain of whole chromosomes. The loss or gain can fatally affect hundreds and even thousands of genes. Some abnormalities support development to term because the chromosome may be small or contain few genes or due to its natural mechanism to help adjust gene dosage. Some of the major abnormalities that support development to term are:

How do Chromosomal Abnormalities occur?

Chromosomal Abnormalities occur when there is an error in cell division. Most of these originate in the egg or sperm (gametes) but some can also happen during embryo development or be inherited from a parent. Chromosomal abnormalities that originate in the gametes are in every cell of the body. 

During the formation of gametes, the two pairs of chromosomes, one each from mother and father, separate in a process called meiosis resulting in one copy of each chromosome in the gametes instead of two. This error in the separation process leads to the formation of gametes with incomplete sets of chromosomes or additional parts of chromosomes and is known as meiotic nondisjunction. 

Other factors that can increase the risk of chromosomal abnormalities include maternal age and factors such as exposure to drugs. 

Treatment for Chromosomal Abnormalities

In several cases, there is no cure for this abnormality. However, some interventions may include:

• Occupational Therapy: The child will need to learn daily skills like bathing, eating, writing, and getting dressed.
• Genetic Counseling: This will help with the know-how of the condition along with its short and long term features. This can help to prevent the risk of recurrence in additional family members.
• Physical Therapy: This can help the child in building strength, improve motor skills, and perform daily tasks.

A common quality among children with chromosomal abnormalities is to either have birth defects or risk for future medical issues. However, treatment can help greatly in dealing with various issues.