In a population of 1000 lizards, 28 are yellow (homozygous recessive, oo) whereas the rest are orange. Orange (O) is the dominant trait and we observe 15 heterozygotes in the population.
Find the phenotype and genotype frequency for OO, Oo, and oo. Find the inbreeding coefficient.
To find the phenotype and genotype frequency for OO, Oo, and oo, as well as the inbreeding coefficient, we can use the following formulas:
1. Phenotype frequency:
- OO: Number of OO individuals / Total population size
- Oo: Number of Oo individuals / Total population size
- oo: Number of oo individuals / Total population size
2. Genotype frequency:
- OO: Number of OO individuals / Total number of individuals with known genotype
- Oo: Number of Oo individuals / Total number of individuals with known genotype
- oo: Number of oo individuals / Total number of individuals with known genotype
3. Inbreeding coefficient:
- (Number of OO individuals * Number of oo individuals) / (Total number of individuals * Total number of individuals with known genotype)
Let's calculate each of these step by step:
1. Phenotype frequency:
- OO: 0 (as given in the question), assuming there are no individuals with the phenotype OO
- Oo: 15 / 1000 = 0.015 (or 1.5%)
- oo: 28 / 1000 = 0.028 (or 2.8%)
2. Genotype frequency:
- OO: 0 (since there are no individuals with the genotype OO)
- Oo: 15 / (15 + 28) = 15 / 43 ≈ 0.349 (or 34.9%)
- oo: 28 / (15 + 28) = 28 / 43 ≈ 0.651 (or 65.1%)
3. Inbreeding coefficient:
- (28 * 28) / (1000 * 43) ≈ 0.183 (or 18.3%)
So, the phenotype and genotype frequencies are as follows:
- Phenotype frequency: OO = 0%, Oo = 1.5%, oo = 2.8%
- Genotype frequency: OO = 0%, Oo = 34.9%, oo = 65.1%
- Inbreeding coefficient: 18.3%