Difference Between Germline Mutation and Somatic Mutation

The key difference between germline mutation and somatic mutation is that the germline mutation inherits to the offspring while somatic mutation is not inherent to the offspring.

DNA is the heredity material of most living organisms. Mutation is a permanent alteration of the nucleotide sequence of a DNA fragment or a gene. Different types of mutations occur in living organisms. Among them, somatic mutations and germline mutations are two main types.  Somatic mutations occur in single body cells while germline mutations occur in gametes. When somatic mutation takes place in a single body cell, it affects only the tissue that derives from the mutated cell. In contrast to that, all body cells affect when the germline mutation takes place. The major difference between germline mutation and somatic mutation is the possibility of these mutations to pass into the offspring or not.

CONTENTS

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

What is Germline Mutation?

Germline mutation is a mutation occurs in germ cells or sex cells or egg and sperms. Since this mutation is present in gametes, it passes to the next progeny. Furthermore, every cell of the entire organism affects by this germline mutation.

However, these mutations can be harmful, can be not harmful or cannot cause any effect on the offspring. Germline mutations can be identified when the genetic disorders appear in offspring. There are several diseases caused by germline mutations such as Sickle cell anaemia, colour blindness, albinism and cystic fibrosis.

What is Somatic Mutation?

Rest of the cells other than the germ or sex cells are the somatic cells of an organism. Somatic mutation is the mutation that occurs in a single body cell. Hence, this type of mutation localizes only to the tissue which derived from the mutated cell. It does not affect every cell of the organism, unlike germline mutation, which affects every cell of the organism.

The observable outcome of the somatic mutation is a patch of phenotypically mutant cells. Therefore, this type of mutation does not pass into offspring.

What are the Similarities Between Germline Mutation and Somatic Mutation?

• Both Germline Mutation and Somatic Mutation take place in the DNA sequence.
• Also, UV radiation, mutagens and chemicals can cause both these mutations.

What is the Difference Between Germline Mutation and Somatic Mutation?

The key difference between germline mutation and somatic mutation is that the germline mutation occurs in gametes while the somatic mutation occurs in a single body cell. Also, the next important difference between germline mutation and somatic mutation is that the germline mutations inherit to the offspring while the somatic mutations do not inherent to the offspring. Furthermore, germline mutations affect every cell of the organism while somatic mutations affect only the tissue derived from the mutated body cell. We can consider this also as a significant difference between germline mutation and somatic mutation.

The below infographic presents more details on the difference between germline mutation and somatic mutation.

Summary – Germline Mutation vs Somatic Mutation

Mutation is an alteration of the DNA sequence of a gene. It can be two types; germline mutation or somatic mutation based on the type of the cell where it occurs. Germline mutation occurs in the sex cells hence, passes into the next generation and affects every cell of the offspring. On the other hand, somatic mutations occur in body cells hence they localize into the tissues derived from the mutated cells. Moreover, they do not inherit into the next generation. Thus, this is the difference between germline mutation and somatic mutation.

Reference:

1.Griffiths, Anthony JF. “Somatic versus Germinal Mutation.” Current Neurology and Neuroscience Reports., U.S. National Library of Medicine, 1 Jan. 1970. Available here 

Image Courtesy:

1.”Inheritance of a germline loss-of-function mutation in a TSG dramatically increases the risk of cancer”By WassermanLab – Own work, (CC BY-SA 4.0) via Commons Wikimedia  
2.”Estimated somatic mutation rates scaling with size”By Aleah F. Caulin, Trevor A. Graham, Li-San Wang, Carlo C – Aleah F. Caulin, Trevor A. Graham, Li-San Wang, Carlo C. (CC BY 4.0) via Commons Wikimedia