Lewin's Genes

Citation

Krebs, J. E., Goldstein, E. S., & Kilpatrick, S. T. (2018). Lewin's Genes XII (12th ed.). Jones & Bartlett Learning.

Chapter Summary

The twelfth edition has thirty chapters in four parts and runs to 838 pages. The publisher describes it as covering gene structure, sequencing, organisation and expression, with expanded coverage of epigenetics, additional research studies and data, and a revised art program with new figures on chromatin structure and function, epigenetics, and regulation by noncoding and microRNAs in eukaryotes. It names its audience as upper-division undergraduate and graduate courses in molecular biology and molecular genetics.

Part 1, Genes and Chromosomes: Chapters 1–3

Chapter 1, "Genes Are DNA and Encode RNAs and Polypeptides", sets the central relationship between gene, RNA and protein. Chapter 2, "Methods in Molecular Biology and Genetic Engineering", gives the techniques used throughout the book. Chapter 3, "The Interrupted Gene", concerns genes that are split into coding and noncoding segments.

Part 1, Genes and Chromosomes: Chapters 4–6

Chapter 4, "The Content of the Genome", and Chapter 5, "Genome Sequences and Evolution", describe what genomes contain and what sequence comparisons show about evolution. Chapter 6, "Clusters and Repeats", deals with gene families and repeated sequences.

Part 1, Genes and Chromosomes: Chapters 7–8

Chapter 7, "Chromosomes", and Chapter 8, "Chromatin", conclude the first part with how DNA is organised in the cell.

Part 2, DNA Replication and Recombination: Chapters 9–12

Chapter 9, "Replication Is Connected to the Cell Cycle", Chapter 10, "The Replicon: Initiation of Replication", Chapter 11, "DNA Replication", and Chapter 12, "Extrachromosomal Replicons", cover how DNA is copied, from the cell-cycle link to initiation and elongation and to replicons outside the chromosome.

Part 2, DNA Replication and Recombination: Chapters 13–16

Chapter 13, "Homologous and Site-Specific Recombination", Chapter 14, "Repair Systems", Chapter 15, "Transposable Elements and Retroviruses" and Chapter 16, "Somatic DNA Recombination and Hypermutation in the Immune System" deal with the rearrangement and repair of DNA.

Part 3, Transcription and Posttranscriptional Mechanisms: Chapters 17–21

Chapter 17, "Prokaryotic Transcription", and Chapter 18, "Eukaryotic Transcription", are followed by Chapter 19, "RNA Splicing and Processing", Chapter 20, "mRNA Stability and Localization" and Chapter 21, "Catalytic RNA".

Part 3, Transcription and Posttranscriptional Mechanisms: Chapters 22–23

Chapter 22, "Translation", and Chapter 23, "Using the Genetic Code", complete the path from RNA to protein.

Part 4, Gene Regulation: Chapters 24–26

Chapter 24, "The Operon", Chapter 25, "Phage Strategies" and Chapter 26, "Eukaryotic Transcription Regulation" cover regulation in bacteria and phage and then in eukaryotes.

Part 4, Gene Regulation: Chapters 27–30

Chapter 27, "Epigenetics I", Chapter 28, "Epigenetics II", Chapter 29, "Noncoding RNA" and Chapter 30, "Regulatory RNA" close the book with chromatin-based regulation and the roles of RNA.

Key Concepts

Part 1: Chapters 1–8

• The interrupted gene: genes split into segments (Chapter 3).
• Genome content and evolution: Chapters 4 and 5.
• Chromosomes and chromatin: how DNA is packaged (Chapters 7 and 8).

Part 2: Chapters 9–16

• The replicon: the unit of replication (Chapter 10).
• Recombination and repair: homologous and site-specific recombination and repair systems.
• Transposable elements and retroviruses: Chapter 15.
• Somatic recombination and hypermutation: in the immune system (Chapter 16).

Parts 3 and 4: Chapters 17–30

• Splicing and RNA processing; catalytic RNA: Chapters 19 and 21.
• The operon: Chapter 24.
• Epigenetics: Chapters 27 and 28.
• Noncoding and regulatory RNA: Chapters 29 and 30.

Critical Analysis

Strengths

• Breadth across molecular biology. Thirty chapters cover genes and chromosomes, replication and recombination, transcription and posttranscriptional processing, and regulation, including chapters on transposable elements, immune-system recombination and catalytic RNA that shorter books may not give separate space.
• Currency in the regulatory chapters. The publisher highlights expanded epigenetics and revised figures on chromatin, epigenetics and noncoding and microRNA regulation, and the book gives two chapters to epigenetics and two to RNA-based regulation.
• Clear target audience. The publisher addresses upper-division undergraduate and graduate courses, which implies prior study of biology and some biochemistry.

Limitations

• Length and level. At 838 pages it is a large book, and its audience is stated as upper-division and graduate courses; readers meeting molecular biology for the first time will find a concise text easier.

Where It Fits in the Course

Lewin's Genes is the largest and most detailed text on the molecular biology list. Fundamental Molecular Biology is a compact text on the core ideas, and Molecular Biology: A Very Short Introduction is a brief overview; either is a gentler first step. Molecular Biology of the Gene and Molecular Biology: Principles of Genome Function are undergraduate textbooks that cover similar ground with attention to the experiments behind each result, so the choice between them and Lewin is largely one of presentation. Molecular Biology: Structure and Dynamics of Genomes and Proteomes approaches the subject through the structures of the molecules, and can be read alongside Lewin's chapters on chromatin and transcription.

How to Use This Book

Read it after introductory genetics, cell biology and biochemistry. A one-semester course can follow the four parts in order, with Chapters 1 and 3 for the basic picture, then Chapters 11, 17–19 and 22 for the central processes of replication, transcription, splicing and translation; Chapters 15, 16 and 21 can be left for later. For the regulatory half, read Chapters 24 and 26 before the two epigenetics chapters. Use Chapter 2 as a reference for the methods whenever they come up.