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Why do skin cells and red blood cells need genetic information for renewal?

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Diagram of a DNA double helix showing its twisted ladder structure, with a close-up of the sugar-phosphate backbone, paired nitrogenous bases (adenine, thymine, cytosine, guanine), and labeled nucleotides and hydrogen bonds. — human genome The human genome is made up of approximately three billion base pairs of deoxyribonucleic acid (DNA). The bases of DNA are adenine (A), thymine (T), guanine (G), and cytosine (C).

Skin cells and red blood cells require genetic information for renewal because they are part of a continuous process of cell differentiation, which is essential for maintaining tissues and organs.1

In multicellular organisms, specialized cells like those in the skin and blood have a limited lifespan and must be constantly repaired or replaced. This renewal relies on stem cells, which contain the complete genetic blueprint necessary to produce new cells. Through a series of complex divisions and transformations, these stem cells differentiate into specialized types.12

This process is strictly regulated by gene expression, where specific signals—such as hormones or growth factors—activate or repress transcription factors to dictate a cell's specialization. For example, in blood cell formation, stem cells in the bone marrow use this genetic information to produce new red blood cells to replace those lost or aged, ensuring the body maintains its vital functions. Without this genetic guidance, the body would be unable to regenerate tissues or sustain the specialized cells required for survival.123