Core Principles of Genomics

Key vocabulary and concepts related to genome sequencing reasons, size variation, gene density, and bioinformatics from the genomics lecture.

Genomics

The study of organisms' genomes, which has changed fundamental ways biology is investigated by allowing rapid and cheap sequencing, often serving as the first step in looking at microbial species.

Metagenomics

The process of sequencing environmental DNA to understand biodiversity and ecosystem function in its natural context.

C-value enigma

The observation that within a group of organisms, there is often very little correlation between the size of the genome and the number of genes that exist.

Transposable elements

Copies of particular repetitive sequences found in large numbers within larger genomes, contributing to genome size without necessarily increasing the count of unique genes.

Heterozygosity

The condition in diploid eukaryotes where the two copies of each chromosome inherited from parents are not identical, resulting in different alleles at specific loci.

Smallest microbial genome

A genome found in relationship with leaf hoppers that contains only a little more than $100,000$ base pairs and approximately $100$ genes.

Mammalian genome size

A genome size clustered around approximately $3$ billion base pairs or gigabases ($3 imes 10^9 ext{ bp}$).

Plant genome size (max mentioned)

A genome size found in some complex plants that reaches approximately $150$ gigabases ($150 imes 10^9 ext{ bp}$) and is filled with repetitive stretches of DNA.

Gene density

A measure of genome structure representing how many genes are found per million bases ($10^6$) of sequence.

Mitochondrial genome

One of the most densely packed genomes in eukaryotic cells, which saves space by occasionally using overlapping genes or incomplete protein-coding sequences that wait for later processing.

Bacterial gene density

A genome structure typically containing between $500$ and $1,000$ genes per million bases.

C. elegans gene density

A nematode genome structure containing approximately $200$ genes per megabase.

Human gene density

A genome structure that is relatively sparse, containing on average only $12$ to $15$ genes per million bases.

Bioinformatics

The field of using computer algorithms to reverse engineer what strings of $G$, $A$, $T$, and $C$ sequences do by applying the rules of transcription and translation.