Final answer:
α-Thalassemia with one gene deleted typically presents very mildly and often without symptoms, as the remaining three genes can usually compensate for the loss. It is often detected only through blood tests or genetic screenings.
Step-by-step explanation:
α-Thalassemia Presentation with One Gene Deleted
α-Thalassemia is a genetic blood disorder characterized by the reduction in the synthesis of alpha-globin chains of hemoglobin. Humans have two pairs of α-globin genes, resulting in a total of four genes. When one gene is deleted or deactivated, the outcome is typically very mild since the other three genes are usually able to compensate for the loss. This condition might not present with any noticeable symptoms and is often discovered only through a routine blood test or a genetic screening. However, the deletion of more genes can lead to more severe forms of thalassemia, which are associated with health complications and require medical intervention. In α-thalassemia with one gene deleted, there may be a slight imbalance in the alpha to beta-globin chain ratio, but it rarely causes significant medical issues. It's worth noting, however, that carriers of one deleted α-thalassemia gene can pass the trait to their offspring, who may be at risk if the other parent also carries a thalassemia gene mutation.