Teacher: 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.
Teacher: Now, understand the problem? If you are still confused, see the following example:
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
Reason: 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.

Now, solve this instance: Context: Neurofibromatosis type 1 (NF1) is characterized primarily by tumor formation in the nervous system, but patients report other neurological complications including pain and itch. Individuals with NF1 harbor 1 mutated NF1 allele causing heterozygous expression in all of their cells. In mice, Nf1 heterozygosity leads to hyperexcitability of sensory neurons and hyperproliferation of mast cells, both of which could lead to increased hypersensitivity and scratching in response to noxious and pruritic stimuli. To determine whether Nf1 heterozygosity may increase pain and itch behaviors independent of secondary effects of tumor formation, we used mice with a targeted, heterozygous Nf1 gene deletion (Nf1) that lack tumors. Nf1 mice exhibited normal baseline responses to thermal and mechanical stimuli. Moreover, similar to wild-type littermates, Nf1 mice developed inflammation-induced heatand mechanical hypersensitivity, capsaicin-induced nocifensive behavior, histamine-dependent or -independent scratching, and chronic constriction injury-induced cold allodynia. However, Nf1mice exhibited an attenuated first phase of formalin-induced spontaneous behavior and expedited resolution of formalin-induced heat hypersensitivity. These results are not consistent with the hypothesis that Nf1 heterozygosity alone is sufficient to increase pain and itch sensation in mice, and they suggest that additional mechanisms may underlie reports of increased pain and itch in NF1 patients. This study assessed whether Nf1 heterozygosity in mice increased hypersensitivity and scratching following noxious and pruritic stimuli. Using Nf1 mice lacking tumors, this study finds no increases in pain or itch behavior, suggesting that there is no predisposition for either clinical symptom solely due to Nf1 heterozygosity.
Question: Which is the gene mutated in type 1 neurofibromatosis?
Student:
nf1