Question

If the frequency of the autosomal dominant allele is 0.6 then calculate the frequency of recessive phenotype in a population of 6000.
A) 1200
B) 4000
C) 960
D) 1000

Answer 1

Hint: The allele is a variant of the gene. Some genes have a variety of different forms, which are located in the same position, or a genetic locus, on a chromosome. Humans are called diploid organisms because they have two alleles in each genetic locus, with one allele inherited from each parent.

Complete answer:
Autosomal dominance is a pattern of inheritance that is characteristic of some genetic diseases. "Autosomal" means that the gene in question is located on one of the numbered or non-sexual chromosomes. "Dominant" means that a single copy of the mutation associated with the disease is sufficient to cause the disease.
In genetics, the predominance is the phenomenon of one variant of the gene masking the chromosome or overcoming the effect of another variant of the same gene on the other copy of the chromosome. The first variant is called dominant and the second recessive.
Dominance is not inherent in an allele or its features (phenotype). It is a strictly relative effect of any function between two alleles of a given gene; one allele may be dominant over the second allele of the same gene, recessive to the third and co-dominant to the fourth. In addition, for one trait, one allele may be dominant, but not the other.
\[
 \Rightarrow p=0.6 \\
 \Rightarrow q=1-0.6 \\
 \Rightarrow q=0.4 \\
 \Rightarrow {{q}^{2}}=0.16 \\
\]
Then, in 6000 individuals
\[
  \Rightarrow \dfrac{16}{100}\times 6000=960 \\
\]

Thus, the answer is option ‘C’ i.e, 960.

Note: If two alleles of a given gene are identical, the organism is called a homozygous and is said to be homozygous with respect to that gene; if the two alleles are different, the organism is heterozygous and heterozygous. The genetic makeup of an organism, either in a single locus or in all its genes together, is called its genotype.