1. Genetic Disorders:
Genes are the building blocks of heredity. They are passed from
parent to child. They hold DNA, the instructions for making proteins.
Proteins do most of the work in cells. They move molecules from one
place to another, build structures, break down toxins, and do many
other maintenance jobs.
Sometimes there is a mutation, a change in a gene or genes. The
mutation changes the gene's instructions for making a protein, so the
protein does not work properly or is missing entirely. This can cause
a medical condition called a genetic disorder.
2. What are The Leading Causes of Genetic Diseases?
Genetic diseases occur due to abnormalities in one or more genes. You may acquire a genetic
mutation during your lifetime. In most cases, mutations are passed down from the parent. A
mutation affects how your genes make proteins. These changes may lead to improper cell
functioning. Listed below are the principal causes of genetic disorders:
1. Mutation in One or Multiple Genes :
The permanent alteration in the gene’s DNA structure is called a mutation. It may be inherited or
may occur spontaneously. Genetic mutations in one gene cause monogenic disorders. Genetic
mutations in multiple genes can cause multifactorial inheritance disorders.
2.Chromosomal Aberrations:
There may be chromosome number or structural abnormalities leading to genetic disorders. Extra or
missing chromosomes and irregularities in their structure may cause genetic diseases.
3. Environmental Factors;
Some mutations may occur due to exposure to certain toxins and radiation. UV rays of the sun and
chemicals associated with smoking may also act as mutagens (environmental factors).
3. Signs And Symptoms of Genetic Diseases:
While the physical symptoms of genetic diseases greatly vary on the type, severity, and
organ affected, here are some general indications:
1. Cognitive deficiencies or inability to process information
2. Behavioural changes
3. Developmental delays
4. Issues in speech, vision, and hearing
5. Physical abnormalities in limbs and facial features
6. Stunted growth
7. Breathing troubles
8. Movement-related problems
9. Difficulty in swallowing and digesting
10. Incidences of seizures and strokes
11. Diminished social skills
12. Unusual birthmark
13. Skeletal deformities
4. Genetic Diseases Types And Examples:
The genetic diseases list is vast, and the causes are diverse. To help us understand them
better, we can group these disorders into four main categories:
1.Monogenetic Inheritance Disorder:
• Genetic diseases occurring due to mutations in the DNA sequence of a single gene are
called monogenetic diseases. The individual may inherit one or two copies of the
defective gene from the parent.
• Examples of this type include sickle-cell anemia, cystic fibrosis, Huntington’s disease,
thalassemia, and Marfan syndrome.
2.Multifactorial Inheritance Disorder:
• Genetic disorders occurring due to mutations in multiple genes are called
multifactorial genetic diseases. Environmental factors may also trigger these
mutations.
• Examples of this type include diabetes, arthritis, hypertension, cardiovascular defects,
and Alzheimer’s disease.
5. 3.Mitochondrial Inheritance Disorder:
• Mitochondria are cell organelles (parts within a cell) involved in cellular
respiration. Alterations in the mitochondrial DNA (always inherited from
the female parent) lead to this genetic disease type.
• Examples of this type include mitochondrial encephalopathy, Leber’s
hereditary optic atrophy, Pearson syndrome, myoclonic epilepsy, and
Leigh’s disease.
4.Chromosomal Genetic Disorder:
• Some genetic disorders arise due to problems during cell division. It results
in irregularities in the number and structure of chromosomes, causing
chromosomal genetic diseases.
• Examples of this type include Down syndrome, Turner syndrome,
Klinefelter syndrome, Cri-du-chat syndrome, and ring chromosome 14
syndrome.
6. How are Genetic Diseases Diagnosed?
Experts recommend genetic counseling and testing if you have a family history of genetic
disorders. You can get a risk assessment done to avert future uncertainties. Here are a few
diagnostic tests conducted to detect genetic disorders:
1.Prenatal tests:
• There are two types of prenatal genetic testing – screening and diagnostic. Screening tests
determine the probability of your baby having genetic disorders. Diagnostic testing of fetal
cells confirms whether that condition is present or not. An example includes non-invasive
prenatal testing (NIPT).
2.Predictive Testing:
• This test is for those who do not have a family history of genetic diseases yet want to rule
out the chances.
3.Testing if you are a Carrier:
• Doctors test the DNA obtained from blood or cheek cells. This test confirms whether you
or your partner carry genes linked to a disorder.
7. 4.Pre-Implantation Testing:
•It is exclusively for those opting for in-vitro fertilization. It
diagnoses the possibility of genetic disorders in an embryo
before implanting it into the uterus.
5.NewBorn Screening (NBS):
•It involves testing for possible chromosomal abnormalities
in a newborn. The diagnosis helps manage the condition
early if detected.
8. Treatment and Prevention of Genetic Diseases:
• The treatment for genetic diseases depends on the kind and severity of
the disorder. While one cannot reverse them, various techniques help
manage the condition better. These include medications, chemotherapy,
blood transfusions, organ transplants, radiation therapies, and surgery.
Occupational therapy and dietary modifications also help.
• Genetic diseases may not be completely curable, but they are preventable.
Genetic counseling and testing are the only ways to assess the risks. They
give an idea of the likelihood of passing these diseases to the future
generation.