Uniparental inheritance

Inheritance pattern involving genes from only one parent

Uniparental Inheritance

Carl Correns, a key figure in the study of uniparental inheritance

Uniparental inheritance refers to a genetic transmission pattern where offspring inherit genes exclusively from one parent. This phenomenon is most commonly observed in the inheritance of mitochondrial DNA and chloroplast DNA, which are typically passed down from the mother in most organisms.

Mechanisms

Uniparental inheritance can occur through several mechanisms:

• Maternal inheritance: This is the most common form, where the mitochondria and chloroplasts are inherited from the mother. In most animals, the egg cell contributes the majority of the cytoplasm, including organelles, to the zygote, while the sperm contributes little more than its nucleus.

• Paternal inheritance: Although rare, some species exhibit paternal inheritance of organelles. This can occur in certain plants and algae where the sperm cell contributes organelles to the offspring.

• Biparental inheritance: In some cases, both parents contribute organelles, but one parent's organelles are selectively degraded or silenced.

Historical Context

The concept of uniparental inheritance was first explored in the early 20th century. Carl Correns, a German botanist, was one of the pioneers in this field. He conducted experiments on plants that demonstrated non-Mendelian inheritance patterns, which led to the understanding of cytoplasmic inheritance.

Implications

Uniparental inheritance has significant implications in various fields:

• Genetic diseases: Many mitochondrial diseases are inherited maternally. Understanding uniparental inheritance helps in diagnosing and managing these conditions.

• Evolutionary biology: The study of uniparental inheritance provides insights into evolutionary processes and the role of organelles in genetic variation.

• Biotechnology: Knowledge of uniparental inheritance is applied in genetic engineering and cloning technologies.

Related Pages

• Mitochondrial DNA
• Chloroplast DNA
• Cytoplasmic inheritance
• Non-Mendelian inheritance