What inheritance pattern is displayed by Duchenne's muscular dystrophy?

• A. Mitochondrial
• B. Y-linked
• C. X-linked recessive
• D. Autosomal dominant

Answer: (C)

Verified step by step guidance

1. Understand the concept of inheritance patterns: In genetics, inheritance patterns describe how a trait or disorder is passed from one generation to the next. Common patterns include autosomal dominant, autosomal recessive, X-linked dominant, X-linked recessive, Y-linked, and mitochondrial inheritance.
2. Identify the characteristics of X-linked recessive inheritance: This pattern occurs when a gene causing a disorder is located on the X chromosome. Males (XY) are more frequently affected because they have only one X chromosome, while females (XX) would need two copies of the recessive allele to express the disorder.
3. Recognize the traits of Duchenne's muscular dystrophy: Duchenne's muscular dystrophy (DMD) is a genetic disorder characterized by progressive muscle degeneration and weakness. It primarily affects males, which is a key indicator of X-linked recessive inheritance.
4. Consider the genetic transmission: In X-linked recessive disorders, an affected male cannot pass the disorder to his sons (since they inherit his Y chromosome), but all his daughters will be carriers. A carrier female has a 50% chance of passing the affected X chromosome to her sons, who will then express the disorder.
5. Conclude the inheritance pattern: Based on the characteristics of Duchenne's muscular dystrophy and the typical transmission pattern, it is classified as an X-linked recessive disorder.