Genetic Monitoring

Question 1

How do C57BL6/J and C57BL6/N mice differ?

Answer 1

Functional deletion of nicotinamide nucleotide transhydrogenase (Nnt) gene in B6/J derived substrains

Question 2

What is genetic drift?

Answer 2

Constant tendency of genes to evolve even in the absence of selective forces. Fueled by spontaneous mutations that disappear or become fixed in a population at random.

Question 3

How can you prevent genetic drift? (3)

Answer 3

1. Breeding schemes using vendor-purchased animals to genetically refresh colonies
2. Cryopreserve sperm and/or embryos
3. Genetically refresh with archived cryopreserved materials.

Question 4

What are microsatellites? Describe their use.

Answer 4

Short DNA sequences that are made up of repeated units of a few base pairs. Also known as short tandem repeats (STRs)
Used to monitor genetic drift. Allele sizes in large number of strains in both mice and rats. Highly polymorphic.

Question 5

What are single nucleotide polymorphisms? Describe their use.

Answer 5

Single nucleotide changes. Have high density across the genome but diallelic, so less polymorphic. Also not well-characterized in the rat.

Question 6

Describe miniMUGA. What is it used for?

Answer 6

Array that uses the most informative SNPs from 120 classical inbred lines. Establish a genetic profiled for the colony and monitor periodically. Can detect genetic contamination and drift.