Question

In regard to guevedoce, why is it important that the parents are related and from the Dominican Republic? How is the disease inherited - mode of inheritance? (To describe the mode of inheritance, you have to determine if it is autosomal or X-linked and dominant or recessive.) Also would you expect the disease to be rare or common? Why?

Answer 1

Guevedoce refers to those children in the Dominican Republic that appear to be born as girls, but are in fact genetically male and are found to develop male genitals upon reaching puberty. It occurs due to the deficiency in the production of an enzyme called 5α-reductase 2. This enzyme is required for the metabolic processing of male hormones such as testosterone, before birth. This deficiency occurs due to a mutation in the SRD5A2 gene (steroid 5 alpha-reductase 2). The inheritance of this mutation (disease) occurs in an autosomal recessive manner, which is both the parents need to carry one mutated SRDA2 gene copy, making them the carriers, who do not have this condition (symptoms). However, the male child is born with genitals that appear female, and later after puberty start developing male genitalia due to the production of more testosterone. This is a rare genetic condition that is found to occur in people living in countries like the Dominican Republic.