The frequency of the sickle cell disease in parts of Central Africa is as high as 10 percent compared to a frequency of .5 percent in the US.

Use the percentages for the Central Africa population and the US population to calculate the frequency of the heterozygous and homozygous dominant genotypes in each of these areas.

Sickle cell anemia is autosomal dominant.

Let p=sickle cell and q=normal cell.

p+q=1

(p+q)^2=p^2+2pq+q^2=1

p^2= homozygous dominant
q^2=sickle cell
2pq=heterozygous

For Central Africa

0.1=q^2=sickle cell
q=0.316
p=1-0.316=0.684

p^2= homozygous dominant=(0.684)^2=0.468
q^2=sickle cell=(0.316)^2=0.0999
2pq=heterozygous=2(0.684)(0.316)=0.432

p^2+2pq+q^2=0.468+0.432+0.0999=1

Repeat for U.S.

how do i do this?

thanks! so the heterozygous and homozygous dominant genotypes are p^2 and 2pq?

Yes, but when you do theses Hardy-Weinberg problems you are suppose to let the recessive gene equal p and the autosomal dominant gene equal q. When I started doing this for you I accidentally switched it, but the numbers are correct. The post should read

Let p=sickle cell and q=normal cell.

p+q=1

(p+q)^2=p^2+2pq+q^2=1

q^2= homozygous dominant
p^2=sickle cell
2pq=heterozygous

For Central Africa

0.1=p^2=sickle cell
p=0.316
q=1-0.316=0.684

q^2= homozygous dominant=(0.684)^2=0.468
p^2=sickle cell=(0.316)^2=0.0999
2pq=heterozygous=2(0.684)(0.316)=0.432

p^2+2pq+q^2=0.0999 +0.432+0.468=1

How would you repeat for the us?

To calculate the frequency of the heterozygous and homozygous dominant genotypes in each of these areas, we need to understand the concept of allele frequencies and use simple genetic calculations.

First, let's define some terms:
- Heterozygous genotype: This means having two different alleles for a particular gene. In the case of sickle cell disease, the heterozygous genotype is called AS, indicating that one allele is for sickle cell trait and the other is normal.
- Homozygous dominant genotype: This means having two identical dominant alleles for a particular gene. In the case of sickle cell disease, the homozygous dominant genotype is called AA, indicating that both alleles are normal.

Now, let's calculate the frequencies in each population:

1. Central Africa:
Given that the frequency of sickle cell disease is 10 percent, we can assume this represents the frequency of the homozygous recessive genotype (SS), as individuals with SS genotype have sickle cell disease.

To find the frequency of the heterozygous genotype (AS), we can subtract the frequency of the homozygous recessive genotype from 100 percent (assuming there are only two possible genotypes, SS and AS).

Hence, the frequency of the heterozygous genotype in Central Africa would be 100% - 10% = 90%.

The frequency of the homozygous dominant genotype (AA) can be assumed to be zero, as having both normal alleles confers resistance to sickle cell disease.

2. United States:
Given that the frequency of sickle cell disease is 0.5 percent, we can assume this represents the frequency of the homozygous recessive genotype (SS).

To find the frequency of the heterozygous genotype (AS), we can repeat the same calculation as above: subtract the frequency of the homozygous recessive genotype from 100 percent.

Hence, the frequency of the heterozygous genotype in the US would be 100% - 0.5% = 99.5%.

Similar to Central Africa, the frequency of the homozygous dominant genotype (AA) would be assumed to be zero.

Therefore, in Central Africa, the estimated frequencies would be:
- Heterozygous (AS): 90%
- Homozygous dominant (AA): 0%

And in the United States, the estimated frequencies would be:
- Heterozygous (AS): 99.5%
- Homozygous dominant (AA): 0%

It's important to note that these calculations are based on the assumption that there are only two possible genotypes (SS and AS) and that the frequencies provided represent the frequency of the SS genotype. Real-world populations may have more complex genetic variations, so these are simplified estimations.