What is hydrops fetalis?
Question: What is hydrops fetalis?
A.5 genes responsible for the synthesis of the alpha-globulin protein in hemoglobin are defective
B.4 genes responsible for the synthesis of the alpha-globulin protein in hemoglobin are defective
C.3 genes responsible for the synthesis of the alpha-globulin protein in hemoglobin are defective
D.2 genes responsible for the synthesis of the alpha-globulin protein in hemoglobin are defective
E.1 gene responsible for the synthesis of the alpha-globulin protein in hemoglobin are defective
Correct Answer is B. There are two genes from each parent (four genes total) responsible for the synthesis of the alpha-globulin protein in hemoglobin. In hydrops fetalis, all four genes are defective, and alpha-globulin is absent.
Alpha-Thalassemia syndromes
| Number of Alpha-Globin Genes Transcribed | Syndrome |
| 4 | Normal |
| 3 | Silent carrier |
| 2 | Thalassemia minor (or trait) |
| 1 | Hemoglobin H disease |
| 0 | Hydrops fetalis |
