NEET Biology Genetics : Mendelian Disorder (Autosomal Recessive, X-lined Dominant and Recessive)

TL;DR

This video explains the concepts of autosomal and sex-linked inheritance in relation to Mendelian disorders, highlighting the importance of the presence of one or two defective genes in determining disease occurrence.

Transcript

hello friends this video on need genetics is brought to you by exams your calm no more fearsome exam type of maintaining disorder is autosomal recessive disorder so this is also Auto so much happens it gets transmitted through the auto zone so this is also independent of genders but in this case a child gets the disease only if he or she inherits t... Read More

Key Insights

• ❓ Autosomal recessive disorders occur when an individual inherits two abnormal genes, while autosomal dominant disorders manifest with just one abnormal gene.
• ☺️ Sex-linked dominant disorders are determined by the presence of a dominant gene on the X chromosome.
• ☺️ Sex-linked recessive disorders require both X chromosomes to carry the defective gene.

Questions & Answers

Q: What is the difference between autosomal recessive and autosomal dominant disorders?

Autosomal recessive disorders require the inheritance of two abnormal genes for disease manifestation, while autosomal dominant disorders occur when one abnormal gene is present.

Q: How are sex-linked dominant disorders inherited?

Sex-linked dominant disorders are inherited when a dominant gene is present on the X chromosome. If one X chromosome carries the defective gene, the individual will have the disease.

Q: Can carriers of autosomal recessive disorders be affected by the disease?

Carriers of autosomal recessive disorders have one normal and one abnormal gene, but they do not exhibit symptoms of the disease. The disease only occurs if both genes are abnormal.

Q: Why are some Mendelian disorders classified as sex-linked recessive?

Sex-linked recessive disorders require both X chromosomes to carry the defective gene for disease manifestation. Males are more prone to these disorders because they have only one X chromosome.

Summary & Key Takeaways

• Autosomal recessive disorders are inherited irrespective of gender, with the disease only manifesting if an individual inherits two abnormal genes.

• Autosomal dominant disorders occur when one abnormal gene is present, causing the individual to be affected by the disease.

• Sex-linked dominant disorders are determined by the presence of a dominant gene on the X chromosome, while sex-linked recessive disorders require both X chromosomes to carry the defective gene.