If both alleles of a gene pair are the same, an individual is considered to have which genetic makeup?

If both alleles of a gene pair are the same, an individual is considered to have which genetic makeup?

• A. Homozygous
• B. Heterozygous
• C. Chimeric
• D. Hemizygous

Answer: (A)

Having two identical alleles at a gene locus is called homozygous. This means the two copies inherited from the parents carry the same variant, such as BB or bb. If the two alleles differ, the individual is heterozygous (for example, Bb). Chimeric describes an organism with two or more different genotypes due to mixtures of zygotes, which is a different situation, and hemizygous refers to having only one copy of a gene at a locus (as seen for many sex-linked genes in males). So, identical alleles across a gene pair define homozygous.

Having two identical alleles at a gene locus is called homozygous. This means the two copies inherited from the parents carry the same variant, such as BB or bb. If the two alleles differ, the individual is heterozygous (for example, Bb). Chimeric describes an organism with two or more different genotypes due to mixtures of zygotes, which is a different situation, and hemizygous refers to having only one copy of a gene at a locus (as seen for many sex-linked genes in males). So, identical alleles across a gene pair define homozygous.