Genetic Disorders

Overview

Genetic disorders are diseases that occur due to mutations in some specific genes. They are mostly inherited from parents to offspring. These conditions arising from changes in the DNA usually have no cure. However, several techniques can effectively manage them to minimise their impact on patients.

What are Genetic Disorders?

Genetic disorders develop when there is a mutation in the normal construct of a gene. The gene is made of Deoxyribonucleic acid, which is further made of codons. The codons are sequences of three nucleotides that code for different proteins during translation. Even a minor change in the nucleotide of a codon results in the formation of a completely different protein and the absence of the required protein. The absence of the required proteins disrupts the normal functioning of the cells, leading to various diseases.

Types of Genetic Disorders

Genetic disorders can be classified into three major types:

Complex (multifactorial): This type of disorder occurs due to mutations in multiple genes in combination with other factors. These factors include diet, chemical exposure, tobacco, certain medications, and alcohol use. Different types of multifactorial disorders include Arthritis, Alzheimer’s disease, autism spectrum disorder, coronary artery disease, cancer, migraine headaches, isolated congenital heart defects, Spina bifida, and so on.

Chromosomal: This type of genetic disorder primarily affects chromosomes that contain the genes. People suffering from this type of genetic disorder either have a missing chromosome or a duplicate chromosome. Some of the chromosomal disorders include Down syndrome, Klinefelter syndrome, Fragile-X syndrome, Triple-X syndrome, Trisomy 18, Turner syndrome, and Trisomy 13.

Single-gene (monogenic): The genetic conditions that fall under this category occur due to the mutation in a single gene. Various single-gene diseases include cystic fibrosis, familial hypercholesterolemia, Duchenne muscular dystrophy, congenital deafness, Hemochromatosis, Sickle cell disease, Neurofibromatosis type 1, and Tay-Sachs disease.

Symptoms of Genetic Disorders

The symptoms of genetic disorders mostly vary with the type of disease and the severity of the condition. However, some common symptoms include breathing problems, behavioural changes or disturbances, the difficulty of the brain in processing information, developmental delays such as challenges in learning social skills or various developmental delays, limb or facial abnormalities, issues in eating and digestion like difficulty in swallowing and processing nutrients, challenges in muscle movement, hearing loss, vision loss, and stunted growth. Upon noticing such symptoms, it is imperative to go for prompt diagnosis to avoid complications.

Causes of Genetic Disorders

The primary cause of genetic disorders is mutation in the genes. The genes are made of DNA which are translated to form essential proteins. These proteins play a key role in the function of cells and their interactions with each other, which play a key role in the body's healthy functioning. When mutations occur, the codons within the DNA get altered, resulting in the absence of the required proteins. Due to this, normal bodily functions get affected, resulting in adverse consequences on the overall health of a person. Some of the popular factors that can cause these genetic mutations include radiation exposure, chemical exposure, smoking, and exposure to UV rays from the sun.

Diagnosis of Genetic Disorders

If a person has a family history of genetic disorder and is planning to have a baby or experiencing certain symptoms, they can visit a doctor for proper diagnosis. Accordingly, they prescribe appropriate lab tests to check for mutations. Also, they can recommend visits to genetic counsellors to understand the risks and the steps to take to manage the condition and avoid passing it on to future generations.

Some of the options for DNA testing for genetic disorders to prevent the inheritance of genetic disorders include:

Prenatal Screening: In this type of testing blood is taken from the pregnant woman and is tested to check if there is a possibility of the foetus being born with a genetic condition.

Carrier Testing: This is another type of blood test that shows if a couple carries a genetic mutation that is likely to pass on from parents to offspring. This test is recommended to every couple planning to have a baby, irrespective of their family history of genetic disorders.

Prenatal Diagnostic Testing: In this test, a sample of amniotic fluid is extracted and put to test to determine if the developing foetus has a risk of developing certain genetic disorders.

Newborn screening: After the birth of the baby, their blood is tested to check if they have any genetic disorders. This helps the doctors identify disease, if present, at an early stage and take the necessary steps to manage it from the very first day.

Treatment for Genetic Disorders

Mostly, there are no permanent cures for genetic disorders. However, early detection of the disease can help doctors prescribe the necessary steps to manage them. The appropriate genetic disorders management and medications depend on the type and severity of the genetic disease. Healthcare providers often prescribe various medications to manage the symptoms associated with genetic disorders. They even prescribe chemotherapy or radiotherapy for slowing down abnormal growth of cells in case of cancer.

Patients are even suggested to go for occupational, physical, or speech therapy to make their daily lives easier. Doctors even prescribe the patient dietary supplements or nutrition counselling to ensure that they get all the necessary nutrients. Furthermore, people are also prescribed blood transfusions to restore healthy blood cells. Healthcare providers also consider surgery and organ transplants as viable options for effective treatments for people suffering from these types of conditions.

Preventive Measures for Genetic Disorders

In the case of genetic disorders, there are no such preventive measures available. Hence, it would be prudent for people who are planning for a baby to consult a genetic counsellor. This will help them know the probability of passing down the genetic disorder and accordingly proceed with family planning.

Myths and Facts Related to Genetic Disorders

Following are some myths associated with genetic disorders and facts bursting the same:

Myth 1: Genetic Disorders Can Only Occur in People with a Family History of That Condition
Fact: Babies can be born with a genetic disorder even when parents do not show any symptoms of the disease. This is so because, in the case of a genetic disorder, either one or both of the parents can be carriers of the disease, which ultimately manifests in their children.

Myth 2: The onset of Genetic Diseases is Always Accompanied by Symptoms
Fact: Not all genetic disorders develop symptoms at an early stage of their onset. Many times, symptoms appear at a later stage or all of a sudden. So, it is mandatory to go for diagnosis immediately after the symptoms appear to effectively manage the symptoms of such diseases.

Myth 3: Genetic Disorders Affect Males and Females Equally
Fact: Not all the time both males and females are at equal risk of developing the diseases. This is mainly true when the disorder is an X-linked disease. This is so because some diseases only happen when there is a mutation in the X chromosome and this mutated chromosome directly passes on from a carrier mother to her son.

Myth 4: Conducting Genetic Testing is Highly Expensive
Fact: With the advancement in technology, genetic testing has become cost-efficient, accurate, and comparatively less time-consuming. Thus, couples who are planning to have a baby must go for genetic testing before moving forward with their decision.

Myth 5: Genetic Testing Will Let People Know About Their Overall Health Condition
Fact: Genetic testing will only offer information regarding the presence of a mutation in the genes of either parent and their chances of passing it on to their child after conceiving. Other than these, genetic testing cannot convey information regarding how the genes interact with each other and their overall health.