A mutation is any alteration in the genetic material of an organism. In general, mutations have a negative impact on the fitness (or reproductive success) of the individual that carries this mutation; however, there are situations where a mutation may be beneficial for the individual in a given environment. When a beneficial mutation occurs in the germline, it potentially can be passed to the next generation and progressively increases its frequency in the population.
Matthew was suffering an anxiety attack, this is proven with his feelings of being "overwhelmed.. feelings of intense apprehension". He was experiencing shortness of breath due to how he was feeling.
