Two-hit hypothesis

The Two-hit hypothesis (pronunciation: /tuː hɪt haɪˈpɒθɪsɪs/) is a genetic theory that explains the mechanism behind the onset of certain types of genetic disorders and cancers.

Etymology

The term "Two-hit hypothesis" was first proposed by Alfred Knudson in 1971. The "two hits" refer to the two genetic alterations or "hits" that are required for a cell to become cancerous.

Explanation

According to the Two-hit hypothesis, both alleles of a tumor suppressor gene must be inactivated or "hit" in order for an effect to be seen. The first "hit" is usually a germline mutation that is present in all cells of an organism from birth. The second "hit" is a somatic mutation that occurs in a single cell during the life of the organism.

Related Terms

Knudson's hypothesis: Another name for the Two-hit hypothesis, named after the scientist who proposed it.
Tumor suppressor gene: A gene that regulates cell division and prevents the formation of tumors.
Germline mutation: A mutation that is present in the egg or sperm cells and can be passed on to offspring.
Somatic mutation: A mutation that occurs in a body cell and cannot be passed on to offspring.

External links

Medical encyclopedia article on Two-hit hypothesis
Wikipedia's article - Two-hit hypothesis

This WikiMD article is a stub. You can help make it a full article.

Languages: - East Asian 中文, 日本, 한국어, South Asian हिन्दी, Urdu, বাংলা, తెలుగు, தமிழ், ಕನ್ನಡ,
Southeast Asian Indonesian, Vietnamese, Thai, မြန်မာဘာသာ, European español, Deutsch, français, русский, português do Brasil, Italian, polski

Two-hit hypothesis