True about Chediak Higashi syndrome is: March 2007
**Core Concept**
Chediak-Higashi syndrome (CHS) is a rare genetic disorder characterized by oculocutaneous albinism, recurrent infections, and bleeding tendencies. It is caused by mutations in the LYST gene, which encodes a protein involved in vesicle formation and function.
**Why the Correct Answer is Right**
The LYST protein plays a crucial role in the regulation of lysosome and melanosomal biogenesis. In CHS, the mutated LYST protein leads to the formation of large, irregularly shaped lysosomes that are unable to fuse with phagosomes, resulting in impaired phagocytosis and increased susceptibility to infections. Additionally, the abnormal lysosomes also affect melanin synthesis, leading to oculocutaneous albinism.
**Why Each Wrong Option is Incorrect**
**Option A:** This option might be incorrect because CHS is not primarily associated with immune deficiency (although it does involve impaired phagocytosis). However, it's worth noting that CHS patients may have some degree of immune dysfunction.
**Option B:** This option is incorrect because CHS is not primarily associated with autoimmune disorders (although some patients may develop autoimmune-like symptoms during the hemophagocytic crisis).
**Option C:** This option is incorrect because CHS is not primarily associated with metabolic disorders (although it does involve impaired lysosomal function).
**Option D:** This option is incorrect because CHS is not primarily associated with connective tissue disorders (although some patients may have some degree of connective tissue involvement).
**Clinical Pearl / High-Yield Fact**
CHS patients are at increased risk of developing a hemophagocytic crisis, a life-threatening condition characterized by excessive immune activation and tissue destruction.
**Correct Answer: B.**