- Adenine (A): Approximately 30.9% of the total base pairs.
- Thymine (T): Approximately 29.4% of the total base pairs.
- Guanine (G): Approximately 19.9% of the total base pairs.
- Cytosine (C): Approximately 19.8% of the total base pairs.
The fact that the percentages of adenine and thymine are close to 30%, and the percentages of guanine and cytosine are close to 20% is known as Chargaff's rule. This rule states that the amount of adenine in DNA is equal to the amount of thymine, and the amount of guanine is equal to the amount of cytosine. This pattern is important for maintaining the structural stability and functionality of DNA molecules.
