What Is A Dimer In DNA?

Pyrimidine dimers are molecular lesions formed from thymine or cytosine bases in DNA via photochemical reactions.

Ultraviolet light (UV) induces the formation of covalent linkages between consecutive bases along the nucleotide chain in the vicinity of their carbon–carbon double bonds.

Why are dimers important to DNA?

Molecule of the Day: Thymine Dimers and Skin Cancer

This makes the molecule potentially very reactive, and in certain situations can result in new bonds being made between different molecules. This is especially important for certain molecules containing pi bonds such as the DNA bases.

How do pyrimidine dimers lead to cancer?

Pyrimidine Dimers

Adducts between two adjacent pyrimidine bases in a DNA strand comprise more than 95% of the DNA lesions caused by UV light below 340 nm wavelength. In man, UV-induced DNA damage is the primary cause of all nonmelanoma skin cancers.

What can cause a thymine dimer and what are the consequences of one forming?

Dangerous Dimers

Ultraviolet light is absorbed by a double bond in thymine and cytosine bases in DNA. The most common reaction is shown here: two thymine bases have formed a tight thymine dimer, with two bonds gluing the bases together.

What’s a thymine dimer?

A pair of abnormally chemically bonded adjacent thymine bases in DNA, resulting from damage by ultra-violet irradiation. The cellular processes that repair this lesion often make errors that create mutations.26 Jul 2004

How do you fix thymine dimers?

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Thymine Dimers – Formation and Repair [HD Animation] – YouTube

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What do thymine dimers cause?

Pyrimidine dimers are molecular lesions formed from thymine or cytosine bases in DNA via photochemical reactions. Ultraviolet light (UV) induces the formation of covalent linkages between consecutive bases along the nucleotide chain in the vicinity of their carbon–carbon double bonds.