Single Gene Disorders | Mendelian Disorders

Summary

This video discusses single-gene disorders, also known as monogenic disorders, which arise from mutations in a single gene and follow Mendelian inheritance patterns. It classifies these disorders into autosomal dominant, autosomal recessive, and X-linked recessive categories, providing examples for each. Key disorders covered include Familial Hypercholesterolemia, Cystic Fibrosis, and Hemophilia A, along with their associated proteins and functions. The video aims to enhance understanding of these genetic conditions, highlighting their impact on health and the importance of genetic research.

Takeaways

• 😀 Single-gene disorders, also known as monogenic disorders, are diseases caused by mutations in a single gene.
• 🧬 These disorders follow Mendelian inheritance patterns, classified into autosomal dominant, autosomal recessive, and X-linked recessive categories.
• 💡 Autosomal dominant disorders include conditions like Familial Hypercholesterolemia and Marfan Syndrome, where one mutated gene can cause the disorder.
• ⚠️ In Familial Hypercholesterolemia, mutations affect the low-density lipoprotein receptor, leading to high cholesterol levels.
• 🏗️ Marfan Syndrome is associated with mutations in the fibrillin protein, impacting connective tissue structure and function.
• 🧠 Neurofibromatosis Type 1 is linked to mutations in the NF1 gene, resulting in neurofibromin production, which regulates cell growth.
• 🌬️ Cystic Fibrosis, an autosomal recessive disorder, is caused by mutations in the CFTR protein, leading to respiratory and digestive complications.
• 🔬 Severe Combined Immunodeficiency (SCID) arises from mutations in adenosine deaminase, affecting immune cell development.
• 🩸 Hemophilia A is an X-linked recessive disorder linked to mutations in Factor VIII, crucial for blood clotting.
• ⚛️ Duchenne Muscular Dystrophy, another X-linked disorder, results from dystrophin mutations that compromise muscle integrity.

Q & A

What are monogenic disorders?

Monogenic disorders, or single-gene disorders, are diseases caused by mutations in a single gene. They follow Mendelian inheritance patterns.

How are monogenic disorders classified?

Monogenic disorders are classified into three categories based on inheritance: autosomal dominant, autosomal recessive, and X-linked recessive.

What is an example of an autosomal dominant disorder?

An example of an autosomal dominant disorder is Huntington's disease, which is caused by mutations in the Huntington gene affecting brain function.

What is Familial Hypercholesterolemia, and how does it affect the body?

Familial Hypercholesterolemia is an autosomal dominant disorder characterized by high cholesterol levels in the blood due to mutations in the low-density lipoprotein (LDL) receptor.

What are the implications of cystic fibrosis?

Cystic fibrosis is an autosomal recessive disorder caused by mutations in the CFTR protein, leading to severe respiratory and digestive issues.

What is the role of the NF1 gene in Neurofibromatosis?

The NF1 gene produces neurofibromin, a protein that regulates cell signaling pathways. Mutations in this gene lead to tumor growth in the nervous system.

Can you explain the significance of the HPRT protein in Lesch-Nyhan Syndrome?

In Lesch-Nyhan Syndrome, there is a deficiency of the HPRT protein, which is crucial for purine metabolism, leading to neurological and behavioral issues.

What causes Sickle Cell Anemia?

Sickle Cell Anemia is caused by mutations in the hemoglobin gene, leading to abnormal hemoglobin that disrupts normal oxygen transport in the body.

What is the difference between autosomal dominant and autosomal recessive inheritance?

In autosomal dominant inheritance, only one mutated gene is needed to cause the disorder, whereas in autosomal recessive inheritance, two copies of the mutated gene are required.

What is Duchenne Muscular Dystrophy, and how is it inherited?

Duchenne Muscular Dystrophy is an X-linked recessive disorder caused by mutations in the dystrophin gene, leading to muscle degeneration and weakness.