G-6-P deficiency occurs in:
**Core Concept**
G-6-PD (Glucose-6-phosphate dehydrogenase) deficiency is a genetic disorder that occurs due to a defect in the **G6PD gene**, leading to a deficiency of the **glucose-6-phosphate dehydrogenase enzyme**. This enzyme plays a crucial role in the **pentose phosphate pathway**, which is essential for generating **NADPH** and protecting red blood cells from oxidative damage.
**Why the Correct Answer is Right**
The correct answer is related to the **X-linked recessive inheritance** pattern of G-6-PD deficiency, which primarily affects males. The deficiency leads to **hemolytic anemia**, particularly in response to certain triggers such as infections, medications, or foods.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because G-6-PD deficiency is not typically associated with this condition.
**Option B:** This option is incorrect as it is unrelated to the **pentose phosphate pathway**.
**Option C:** This option is incorrect because it does not accurately describe the **genetic basis** of G-6-PD deficiency.
**Clinical Pearl / High-Yield Fact**
G-6-PD deficiency is a common cause of **hemolytic anemia** worldwide, and its diagnosis is crucial for preventing complications. Patients with G-6-PD deficiency should avoid certain medications and foods that can trigger hemolysis.
**Correct Answer:** D. Red blood cells