What is the Origin of Parental Imprinting?

The concept emerged from genetic studies in the late 20th century, where researchers observed non-Mendelian inheritance patterns for specific traits, demonstrating that the parental origin of the gene mattered. The term 'imprinting' reflects the idea that a molecular mark is placed on the gene during gametogenesis that dictates its expression status in the offspring.

What is the Mechanism of Parental Imprinting?

The molecular basis of imprinting involves the differential methylation of specific regions of the DNA, known as imprinting control regions (ICRs), in the sperm and egg. These methylation patterns are stable throughout the life of the organism and are crucial for regulating gene dosage. Disruptions to this delicate epigenetic marking, which can be influenced by parental hormonal and nutritional status, are associated with various developmental disorders and metabolic diseases.

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Parental Imprinting

Meaning

Parental imprinting, or genomic imprinting, is an epigenetic phenomenon where the expression of a specific gene is determined solely by the parent from which it was inherited, either the mother or the father. This means that only one allele of the gene is active, while the other is silenced through epigenetic modifications like DNA methylation, which are established in the parental germline. This process is essential for normal fetal development and the regulation of growth, metabolism, and certain neurobehavioral functions.