False statement with regards to given condition is
**Condition:** **Hypokalemic Periodic Paralysis (HPP)**
**Core Concept**
Hypokalemic Periodic Paralysis (HPP) is a genetic disorder characterized by episodes of muscle weakness and paralysis associated with low potassium levels. It is primarily caused by mutations in the calcium channel genes, particularly **CACNA1S** and **CACNB4**, which regulate calcium influx into muscle cells.
**Why the Correct Answer is Right**
During episodes of HPP, the mutated calcium channels lead to an abnormal influx of calcium ions into muscle cells, causing hyperexcitability and muscle contraction. This results in muscle weakness and paralysis. The low potassium levels (hypokalemia) are a secondary effect of the abnormal calcium influx, which triggers the release of potassium ions from muscle cells.
**Why Each Wrong Option is Incorrect**
**Option A:** This statement is incorrect because HPP is primarily caused by mutations in calcium channel genes, not sodium channel genes.
**Option B:** This statement is incorrect because HPP is characterized by low potassium levels, not high potassium levels.
**Option C:** This statement is incorrect because HPP is not caused by mutations in the **SCN4A** gene, which is associated with another condition called hyperkalemic periodic paralysis.
**Clinical Pearl / High-Yield Fact**
HPP is often associated with mutations in the **CACNA1S** gene, which codes for the alpha subunit of the L-type calcium channel. This makes it an important consideration in the differential diagnosis of patients with episodic muscle weakness and hypokalemia.
**Correct Answer: B. Low potassium levels are a primary cause of HPP.**