Difference Between Wobble and Degeneracy

The key difference between wobble and degeneracy is that wobble refers to the hypothesis that explains the non-Watson and crick pairing during codon and anticodon binding between mRNA and tRNA. Meanwhile, the degeneracy of the codon is the ability to produce a single amino acid from multiple codons.

The central dogma of molecular biology explains the process in which the expression of functional proteins takes place. And, this process is a sequence of different steps, including the replication of the genetic material followed by the transcription of the DNA sequence into the mRNA sequence and translation of the mRNA sequence into an amino acid sequence.

In translation, the concepts of the wobble hypothesis and the degeneracy of the codon play important roles. Wobble refers to the ability of single tRNA to recognize more than one codon. It gives rise to the degeneracy of codons. Degeneracy is the phenomenon in which one amino acid may be specified by more than one codon. In simple words, degeneracy refers to the existence of multiple codes for a single amino acid.

CONTENTS

1. Overview and Key Difference
2. What is Wobble
3. What is Degeneracy
4. Similarities Between Wobble and Degeneracy
5. Side by Side Comparison – Wobble vs Degeneracy in Tabular Form
6. Summary

What is Wobble?

The wobble hypothesis is an important hypothesis that explains the non-Watson Crick base pairing that takes place during the translation process. Here, the translation is the molecular process that converts the mRNA codon into an amino acid sequence. According to this hypothesis, the first base of the tRNA anticodon is capable of pairing with the third base of the codon in the mRNA strand by non-Watson and Crick pairing pattern. Thus, they do not follow the conventional adenine-uracil binding or cytosine-guanine binding patterns. It is known as the wobbling pattern of the base 1 of the anticodon and the base 3 of the codon.

The wobble pairings include Adenine and inosine pairing instead of uracil. Uracil pairs with Adenine, Guanine and Inosine. Likewise, Guanine and cytosine are also capable of pairing with inosine. Thus, inosine in tRNA is one of the unusual bases that undergo wobble base pairing.

The wobble base pair binding is less strong as it does not necessarily follow Watson and Crick complementary binding. Furthermore, this concept gives rise to the principle of the degeneracy of the genetic code.

What is Degeneracy?

Degeneracy of the genetic code refers to the redundancy of the genetic code. Thus, there can be many base pair combinations specifying a single amino acid. Generally, the codon of organisms consists of three nucleotide bases. In the concept of degeneracy, these three base combinations may alter although they give rise to the same amino acid. Besides, there are more than 20 codons even though there are only 20 amino acids in nature. Hence, degeneracy explains the existence of multiple codons for a specific amino acid.

In degeneracy, the third base may alter between two codons. Thus, glutamic acid is specified by both the codons GAA and GAG, while leucine is specified by the codons UUA, UUG, CUU, CUC, CUA and CUG.

Therefore, the concept of degeneracy is very important in mutation rates. Due to this, point mutations that take place in the genome can be tolerated and still appear to be silenced. Thus, this type of point mutations does not result in a mutation or alteration of the amino acid sequence. However, if the point mutations lead to an alternation of the amino acid encoded, it might cause severe genotypic and phenotypic changes.

What are the Similarities Between Wobble and Degeneracy?

• Both are important hypotheses that are put forward to explain the central dogma of life in relation to the translation process.
• Moreover, both processes play an important role in translating the three base pair codon language to the 20 amino acid sequence.
• These processes also help the evolutionary patterns of organisms.

What is the Difference Between Wobble and Degeneracy?

The key difference between wobble and degeneracy is primarily the fact that wobbling results in the degeneracy of the genetic code. Wobbling refers to the follow of non-Watson and Crick pairing between the codon’s 3^rd base and the anticodon’s 1^st base. In contrast, degeneracy is the ability of many triplet codon combinations to encode a single amino acid.

The below infographic summarizes the difference between wobble and degeneracy.

Summary – Wobble vs Degeneracy

Wobble hypothesis and degeneracy of the genetic code are two important concepts in the phenomenon of translation. Here, the translation is the process of converting triplet codons into amino acids. In the binding of the codon to the anticodon, the discovery of non-Watson and Crick base pairing refers to the wobble hypothesis. The wobbling of bases between the codon and the anticodon is described by this. In contrast, the degeneracy of the genetic code that results in the wobbling process is the phenomenon where a single amino acid is encoded by many different codons. So, this is the summary of the difference between wobble and degeneracy.

Reference:

1. Griffiths, Anthony JF. “Genetic Code.” An Introduction to Genetic Analysis. 7th Edition., U.S. National Library of Medicine, 1 Jan. 1970, Available here.

Image Courtesy:

1. “Wobble” By Fdardel – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “ELLIPTICAL GENETIC CODE Ian” By Doug Youvan, Frank Layden – Own work derived from File:Hydropathy_Molar_Volume_Genetic_Code_2.png (CC BY-SA 4.0) via Commons Wikimedia