Genetic Disorders

Genetic disorders are due to alterations or abnormalities in the genome of an organism. A genetic disorder may be caused by a mutation in a single gene or multiple genes. It can also be due to changes in the number or structure of chromosomes.

Genes are the basic unit of heredity. They hold the genetic information in the form of DNA which can be translated into useful proteins to carry out life processes. These genes undergo a mutation sometimes, which changes the instructions to formulate the protein, due to which the protein does not work properly. Such disorders are known as genetic disorders.

Some genetic disorders are innate, i.e., present by birth, while others are acquired due to mutations in a particular gene. The genetic disorders that are present by birth are inherited from parents, e.g. cystic fibrosis, haemophilia, sickle cell anaemia, etc. The genetic disorders that are acquired during the lifetime are not inherited from parents, these occur due to mutations that occur randomly or due to exposure to certain chemicals, environments or radiations such as cigarette smoke, UV radiations, etc. Cancer is one such disease.

The genetic disorders can be categorized into two types, namely Mendelian Disorders, i.e., a disorder in a single gene that follows Mendelian inheritance pattern, and Chromosomal Disorders, i.e., damage or alteration in the chromosomes structure or number, the chromosomes are either missing, duplicated or a part is translocated.

Let us explore genetic disorder notes to know about the different types of genetic disorders.

Types of Genetic Disorders

Mendelian Disorder

  • These disorders occur due to mutations in a single gene and can be easily detected by pedigree analysis.

  • These disorders can be autosomal dominant, autosomal recessive, sex-linked dominant, sex-linked recessive, and mitochondrial.

The most common Mendelian disorders include:

  • Cystic fibrosis (autosomal recessive)

  • Haemophilia (sex-linked recessive)

  • Albinism (autosomal recessive)

  • Sickle cell anaemia (autosomal recessive)

Chromosomal Disorder

  • These disorders are caused by any alteration in the number or structure of the chromosomes.

  • Sometimes the whole chromosome is gained or lost.

  • This type of disorder is usually fatal and affects many genes.

Some of the major chromosomal abnormalities are:

  • Down’s syndrome- the addition of a chromosome 21 (trisomy)

  • Turner’s syndrome-absence of an X chromosome (XO)

  • Kleinfelter’s syndrome-addition of an X chromosome (XXY)

Multifactorial Genetic Inheritance

This is also known as polygenic inheritance. These are caused as a result of environmental factors and gene mutations. Some of the examples of this kind of disorder are:

  • Heart disease

  • High blood pressure

  • Alzheimer’s disease

  • Obesity

  • Diabetes

  • Cancer

  • Arthritis

Mitochondrial Inheritance

This type of genetic disorder is caused by mutations in the non-nuclear mitochondrial DNA. The mitochondrial DNA is inherited from the mother. Some of the diseases caused due to mitochondrial inheritance are:

  • Leber’s Hereditary Optic Atrophy (LHON)

  • Myoclonic epilepsy with ragged red fibres

  • Mitochondrial encephalopathy

  • Lactic acidosis

Genetic Counselling

Genetic counselling is one of the remarkable ways of detecting whether a child to be born will be having a genetic disease, or if the person is going to have a genetic disorder. Genetic counsellors can help a person with the diagnosis and treatment of a particular disorder.

Some genetic disorders have been treated by gene therapy. Few of the techniques are under trial and will soon be implemented in medical science to cure genetic disorders.

There are many reasons one should go for genetic counselling:

  • Family history or a previous child with a genetic disease, heart defects, mental retardation, defect in the neural tube, short height, psychiatric disorders, cancer, etc.

  • A parent with an autosomal dominant disease.

  • If the pregnant lady is 35 years or older.

  • Mother suffering from any disorder such as depression, alcoholism, diabetes, thyroid, schizophrenia, etc.

List of Genetic Disorders

Following is the list of genetic disorders that occur in humans:

  1. Cystic fibrosis
  2. Thalassemia
  3. Huntington’s disease
  4. Hemochromatosis
  5. Turner’s syndrome
  6. Kleinfelter’s syndrome
  7. Leber’s Hereditary Optic Atrophy
  8. Cancer
  9. High Blood Pressure
  10.   Obesity

For more information on Genetic Disorders and a list of genetic disorders, register at BYJU’S and refer to the genetic disorder notes for reference.

Acidity is another such problem that arises due to unhealthy eating and lifestyle habits. It is a condition where the acid levels in your stomach increase. When one suffers from this condition, it is important to get treated to avoid all the uncomfortable symptoms, such as constipation, indigestion, vomiting, a feeling of restlessness, etc. For a complete cure in an all-natural way, it is best that you opt for acidity treatment in Ayurveda. It will not only help provide relief but will also enhance your health. A few Ayurvedic remedies for acidity are;

  • Drink tender coconut water twice a day.
  • Take unrefined sugar, green cardamom, and fennel seeds in equal parts. Grind it into a fine powder. Whenever you experience the acidity or heartburn, consume this powder in a glass of cold milk.
  • Take equal parts of cumin seeds and coriander seeds. Now, mix it with equal amounts of sugar. i.e. the cumin-coriander and sugar ratio must be 1:1. Put the mixture in a grinder and powder it finely. Consume this mixture twice a day to get rid of acidity.