First semester:
NAME: TARFA
BASRI
Department : BS ACCOUNT & FIANCE
SUBJECT : BASIC HEALTH AWARENESS
• GENETIC DISORDERS
• 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.
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• 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 t he
protein, due to which the protein does not work properly. Such disorders are known as genetic disorders.
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• Some genetic disorders are innate, i.e., present by birth, while others are acquired due to mutations in a particular gene. T he 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 rando mly or
due to exposure to certain chemicals, environments or radiations such as cigarette smoke, UV radiations, etc. Cancer is one s uch
disease.
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• The genetic disorders can be categorized into two types, namely Mendelian Disorders, i.e., a disorder in a single gene that f ollows
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 trans located.
EXPLORE GENETIC DISORDERS
• 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, 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
• 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)
KIND OF DISORDERS
• 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
• 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:
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• Leber’s Hereditary Optic Atrophy (LHON)
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• Myoclonic epilepsy with ragged red fibres
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• Mitochondrial encephalopathy
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• Lactic acidosis
• GENETIC COUNSELLING
• 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.
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• 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.
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• There are many reasons one should go for genetic counselling:
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• 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.
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• A parent with an autosomal dominant disease.
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• If the pregnant lady is 35 years or older.
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• Mother suffering from any disorder such as depression, alcoholism, diabetes, thyroid, schizophrenia,
etc.
GENETIC DISORDERS
• List of Genetic Disorders Following is the list of genetic disorders that occur in
humans
• Cystic fibrosis
• Thalassemia
• Huntington’s disease
• Hemochromatosis
• Turner’s syndrome
• Kleinfelter’s syndrome
• Leber’s Hereditary
• Optic Atrophy
• Cancer
• High Blood Pressure
• Obesity
