A Step-by-Step Guide to Assemble a Reptilian Genome

Area of Science:

• Genomics
• Bioinformatics
• Comparative Genomics

Background:

• Existing vertebrate genome sequencing and assembly technologies often yield results of lower quality compared to established standards like the human genome.
• There is a need for robust protocols to generate high-quality genome assemblies for diverse vertebrate species, particularly non-model organisms.

Purpose of the Study:

• To present a detailed, step-by-step protocol for de novo sequencing and assembly of a high-quality snake genome.
• To provide a adaptable methodology for sequencing and assembling other reptilian and avian genomes.
• To improve the contiguity and quality of vertebrate genome assemblies.

Main Methods:

• Combining high-depth short-read sequencing with multiple insert size libraries for enhanced scaffolding.
• Integrating optical mapping to further improve scaffold contiguity.
• Developing specific protocols for extracting long DNA molecules from reptilian blood.

Main Results:

• Achieved a significant improvement in the corn snake scaffold N50, increasing it from 3.7 kbp to 1.4 Mbp.
• The resulting genome assembly is among the most contiguous snake genomes reported to date.
• Demonstrated the protocol's effectiveness for producing high-quality genome assemblies in non-model vertebrates.

Conclusions:

• The presented protocol effectively generates high-quality vertebrate genome sequences and assemblies.
• This methodology is transferable to other reptilian and avian species, advancing comparative genomics.
• The combination of short reads, long libraries, and optical mapping is crucial for superior genome assembly quality.