Detailed Instructions: 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.
See one example below:
Problem: Context: Architecturally, the school has a Catholic character. Atop the Main Building's gold dome is a golden statue of the Virgin Mary. Immediately in front of the Main Building and facing it, is a copper statue of Christ with arms upraised with the legend 'Venite Ad Me Omnes'. Next to the Main Building is the Basilica of the Sacred Heart. Immediately behind the basilica is the Grotto, a Marian place of prayer and reflection. It is a replica of the grotto at Lourdes, France where the Virgin Mary reputedly appeared to Saint Bernadette Soubirous in 1858. At the end of the main drive (and in a direct line that connects through 3 statues and the Gold Dome), is a simple, modern stone statue of Mary.
Question: To whom did the Virgin Mary allegedly appear in 1858 in Lourdes France?
Solution: Saint Bernadette Soubirous
Explanation: This is the correct answer. Because the question is asking for the name of the person and following sentence from the passage answers it: It is a replica of the grotto at Lourdes, France where the Virgin Mary reputedly appeared to Saint Bernadette Soubirous in 1858.

Problem: Context: Alzheimer's disease (AD) is a complex neurodegenerative disorder characterized by extracellular plaques containing amyloid (A)-protein and intracellular tangles containing hyperphosphorylated Tau protein. Here, we describe the generation of inducible pluripotent stem cell lines from patients harboring the London familial AD (fAD) amyloid precursor protein (APP) mutation (V717I). We examine AD-relevant phenotypes following directed differentiation to forebrain neuronal fates vulnerable in AD. We observe that over differentiation time to mature neuronal fates, APP expression and levels of A increase dramatically. In both immature and mature neuronal fates, the APPV717I mutation affects both - and -secretase cleavage of APP. Although the mutation lies near the -secretase cleavage site in the transmembrane domain of APP, we find that -secretase cleavage of APP is elevated leading to generation of increased levels of both APPs and A. Furthermore, we find that this mutation alters the initial cleavage site of -secretase, resulting in an increased generation of both A42 and A38. In addition to altered APP processing, an increase in levels of total and phosphorylated Tau is observed in neurons with the APPV717I mutation. We show that treatment with A-specific antibodies early in culture reverses the phenotype of increased total Tau levels, implicating altered A production in fAD neurons in this phenotype. These studies use human neurons to reveal previously unrecognized effects of the most common fAD APP mutation and provide a model system for testing therapeutic strategies in the cell types most relevant to disease processes.
Question: Which disease the London mutation involved in?
Solution:
alzheimer's disease