Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.
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Question: Context: The United States Exploring Expedition was an exploring and surveying expedition of the Pacific Ocean and surrounding lands conducted by the United States from 1838 to 1842.
Question: On what date did United States Exploring Expedition end?

Answer: 1842

Question: Context: NeXTSTEP (also stylized as NeXTstep, NeXTStep, and NEXTSTEP) is a combination of several parts: a Unix operating system based on the Mach kernel, plus source code from BSD Display PostScript and a proprietary windowing engine the Objective-C language and runtime an object-oriented (OO) application layer, including several ''kits'' development tools for the OO layers NeXTSTEP is notable for having been a preeminent implementation of the latter three items.
Question: What is the programming language for NeXTSTEP?

Answer: objective-c

Question: Context: LYST is a large cytosolic protein that influences the biogenesis of lysosome-related organelles, and mutation of the encoding gene, LYST, can cause Chediak-Higashi syndrome. Recently, Lyst-mutant mice were recognized to also exhibit an iris disease resembling exfoliation syndrome, a common cause of glaucoma in humans. Here, Lyst-mutant iris phenotypes were used in a search for genes that influence Lyst pathways. In a candidate gene-driven approach, albino Lyst-mutant mice homozygous for a mutation in Tyr, whose product is key to melanin synthesis within melanosomes, exhibited complete rescue of Lyst-mutant iris phenotypes. In a genetic background-driven approach using a DBA/2J strain of congenic mice, an interval containing Tyrp1 enhanced Lyst-dependent iris phenotypes. Thus, both experimental approaches implicated the melanosome, an organelle that is a potential source of oxidative stress, as contributing to the disease phenotype. Confirming an association with oxidative damage, Lyst mutation resulted in genetic context-sensitive changes in iris lipid hydroperoxide levels, being lowest in albino and highest in DBA/2J mice. Surprisingly, the DBA/2J genetic background also exposed a late-onset neurodegenerative phenotype involving cerebellar Purkinje-cell degeneration. These results identify an association between oxidative damage to lipid membranes and the severity of Lyst-mutant phenotypes, revealing a new mechanism that contributes to pathophysiology involving LYST.
Question: Which syndrome is associated with mutations in the LYST gene?

Answer:
chediak-higashi syndrome