Gene and Genome annotation

Question 1

What is gene annotation?

Answer 1

The process of finding and designating locations of genes on raw DNA sequences

Question 2

What are the two reasons that gene annotation has improved in the last 30 years?

Answer 2

1. Build up of a reference dataset
2. The exponential growth in computer processing

Question 3

What are the two types of gene annotation?

Answer 3

Structural and Functional

Question 4

What is structural annotation?

Answer 4

It maps out the what and where (their structure, coding regions, and locations of regulatory sequences)

Question 5

What is functional gene annotation?

Answer 5

It explores the how and why of genes (biological/chemical function and regulations)

Question 6

What database is built to describe the functions of genes across different species?

Answer 6

The Gene Ontology Database

Question 7

What are the 3 mains aspects of the Gene ontology database?

Answer 7

1. Molecular function - activities performed by products
2. Biological process - biological objectives
3. Cellular Component - locations within cells where gene products are active

Question 8

Why are eukaryote genes complex?

Answer 8

They have large numerous intergenic regions and introns

The coding regions compose only a minor portion of the gene

Question 9

What is cDNA?

Answer 9

It is a form of synthesized complementary DNA from RNA

Question 10

What is the process of making cDNA called?

Answer 10

Reverse transcription

Question 11

What is the point of cDNA?

Answer 11

It has already spiced out the introns, so its just exons and some UTR regions

Question 12

What is the error rate of splice annotation?

Answer 12

1/150-250

Question 13

Why are prokaryotic genes easier to annotate than eukaryotic?

Answer 13

They typically lack introns

Question 14

How many reading frames as there in DNA?

Answer 14

6 (3 in the top, 3 on the bottom)

Question 15

What is evidence that an ORF will encode a protein?

Answer 15

1. It encodes a protein similar to a previously described one
2. It is preceded by a typical promoter
3. It is preceded by a typical ribosome-binding site