Question

If the characteristic followed in the pedigree is autosomal recessive, what is III-1's genotype?

a. Either homozygous dominant or heterozygous
b. Definitely heterozygous
c. Definitely homozygous dominant
d. Must be homozygous recessive
e. Homozygous dominant since he is a male but a female would be heterozygous

Answer 1

For an autosomal recessive trait, III-1's genotype could be homozygous recessive if they express the trait. If they don't express it, they could be either homozygous dominant or heterozygous.

Step-by-step explanation:

If the characteristic followed in the pedigree is autosomal recessive, and we are considering III-1's genotype, there are several possibilities depending on the genotype of III-1's parents and whether or not III-1 expresses the trait.

A recessive trait will only be observed in individuals that are homozygous recessive for that trait (aa). For III-1 to express an autosomal recessive disease, they must be homozygous recessive. If III-1 is not expressing the disease, they could either be homozygous dominant (AA) or heterozygous (Aa). However, without additional context or pedigree analysis, we cannot determine whether III-1 is homozygous dominant or heterozygous.

It is important to note that the sex of the individual does not affect the inheritance of autosomal traits, therefore suggesting a different genotype based on gender would not be accurate. Both males and females would follow the same pattern of inheritance for an autosomal trait.