The mutation associated with X linked Alpo Syndrome is:
**Core Concept**
X-linked Alport Syndrome is a genetic disorder characterized by progressive kidney disease, hearing loss, and eye abnormalities. It is caused by mutations in the COL4A5 gene, which encodes a type IV collagen protein essential for the integrity of the glomerular basement membrane in the kidneys.
**Why the Correct Answer is Right**
The COL4A5 gene is located on the X chromosome, and mutations in this gene lead to the production of abnormal type IV collagen proteins. These abnormal proteins accumulate in the glomerular basement membrane, causing thickening and scarring, which disrupts the normal filtration process in the kidneys. The defective collagen also disrupts the normal structure of the glomerular basement membrane, leading to hematuria (blood in the urine) and progressive kidney disease.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because Alport Syndrome is not associated with mutations in the COL4A3 or COL4A4 genes, although these genes are also involved in the production of type IV collagen. Mutations in these genes are associated with autosomal forms of Alport Syndrome.
* **Option B:** This option is incorrect because the mutation associated with X-linked Alport Syndrome is not in the COL4A6 gene, which is involved in the production of type IV collagen in the eyes and ears.
* **Option C:** This option is incorrect because the mutation associated with X-linked Alport Syndrome is not in the COL4A2 gene, which is involved in the production of type IV collagen in the blood vessels and other tissues.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that X-linked Alport Syndrome is caused by mutations in the COL4A5 gene, and it's inherited in an X-linked recessive pattern, meaning that males are more frequently affected than females.
**Correct Answer: C. COL4A5 gene**