Which of the following is an autosomal dominant metabolic disorder-
**Core Concept**
Autosomal dominant metabolic disorders are characterized by mutations in genes that result in the production of abnormal proteins or enzymes, leading to metabolic imbalances. These disorders often exhibit dominant inheritance patterns, where a single copy of the mutated gene is sufficient to cause the condition.
**Why the Correct Answer is Right**
The correct answer is **Cystinuria**, an autosomal dominant disorder caused by mutations in the SLC3A1 or SLC7A9 genes. This disorder leads to the excessive excretion of cystine and other dibasic amino acids in the urine, resulting in the formation of cystine stones. The mutation disrupts the function of the rBAT (SLC3A1) and 4F2hc (SLC7A9) protein complex, which is responsible for the reabsorption of cystine and other dibasic amino acids in the proximal tubules of the kidneys.
**Why Each Wrong Option is Incorrect**
**Option A:** **Familial Hypercholesterolemia** is an autosomal dominant disorder, but it is primarily a lipid metabolism disorder, not a metabolic disorder in the classical sense.
**Option B:** **Glycogen Storage Disease Type I (Von Gierke's disease)** is an autosomal recessive disorder, not autosomal dominant.
**Option D:** **Hypophosphatemic Rickets** is an X-linked dominant disorder, not autosomal dominant.
**Clinical Pearl / High-Yield Fact**
Cystinuria is an important example of a metabolic disorder that can be managed with a combination of dietary modifications and medication to prevent the formation of cystine stones. Patients with cystinuria should avoid a high-meat diet and follow a low-cystine diet to reduce the risk of stone formation.
**Correct Answer:** C. Cystinuria.