Given: Mammalian Genome
• 3 × 109 bps
• 1 × 104 genes
• 1 × 104 bp/gene
1. Calculating for the total number of base pairs in mammalian genes:
= 1 × 108 base pairs
Answer: There are 1 × 108 base pairs in mammalian genes.
• There are approximately 3,000,000,000 base pairs in the mammalian genome (genes constitute only a small portion of this total).
• There are approximately 10,000 genes in the mammalian genome.
• A single gene averages about 10,000 base pairs in size.
1. Based on the assumptions above, in the mammalian genome, how many total base pairs are in all the mammalian genes? Show your math.
2. What proportion (%) of the total genome does this represent? Show your math.
3. What is the probability that a random mutation will occur in any given gene? Show your math.
4. Only 1 out of 3 mutations that occur in a gene result in a change to the protein structure. What is the probability that a random mutation will change the structure of a protein? Show your math.