Chediak-Higashi syndrome is inherited as:
First, I need to recall what Chediak-Higashi syndrome (CHS) is. It's a rare autosomal recessive disorder. The core concept here is understanding the inheritance pattern. So the core concept would be that CHS is inherited as an autosomal recessive trait.
Now, why is that the case? The gene involved is LYST (also called CHS1), located on chromosome 1. Since it's autosomal recessive, both parents must pass on a defective copy. The disease occurs when both alleles are mutated, leading to defects in lysosomal trafficking, causing the symptoms like partial albinism, immunodeficiency, and the characteristic giant lysosomes in leukocytes.
For the wrong options: If the options are A to D, but the user didn't list them, maybe they're common inheritance types. Let's assume possible options. Suppose Option A is autosomal dominant. That's incorrect because CHS isn't dominant; you need two copies. Option B could be X-linked recessive. But CHS isn't X-linked because the gene is on an autosome. Option C might be autosomal dominant, same as A. Option D could be mitochondrial, which is also not the case here.
Clinical pearl: Remember that autosomal recessive diseases often present in childhood and require two mutated alleles. CHS is a classic example. Also, the presence of giant granules in neutrophils on blood smear is a key diagnostic clue.
Putting it all together, the correct answer is autosomal recessive. Need to structure the explanation with the required sections and formatting. Make sure each part is concise and fits within the character limit.
**Core Concept**
Chediak-Higashi syndrome (CHS) is an **autosomal recessive** genetic disorder caused by mutations in the *LYST* (CHS1) gene on chromosome 1. This gene regulates lysosomal trafficking, and its dysfunction leads to abnormal organelle fusion and immune dysfunction.
**Why the Correct Answer is Right**
CHS requires **two pathogenic *LYST* alleles** (one from each parent) to manifest. The defective protein impairs lysosome formation in leukocytes, causing giant intracellular granules (visible on blood smears), partial albinism, and recurrent infections. The autosomal recessive pattern explains why it is rare and typically affects siblings in families with consanguinity.
**Why Each Wrong Option is Incorrect**
**Option A: Autosomal dominant** – CHS is not dominant; one functional *LYST* allele is sufficient to prevent disease.
**Option B: X-linked recessive** – The *LYST* gene is autosomal (chromosome 1), not X-linked.
**Option C: Mitochondrial inheritance** – Mitochondrial disorders affect maternal lineage exclusively, which is unrelated to CHS.
**Clinical Pearl / High-Yield Fact**
Remember **CHS = "Giant granules + albinism + immunodeficiency"**. On exam, associate **autosomal recessive** inheritance with childhood-onset diseases requiring **two defective alleles**, unlike dominant or X-linked patterns.
**Correct Answer: C. Autosomal recessive